Working machine

ABSTRACT

A floor mat arranged in a working machine includes a floor portion, a wall portion arranged on a circumferential portion of the floor portion, and an opening portion arranged on a part of a connecting portion of the wall portion, the connecting portion connecting to the floor portion. The floor mat includes a mat main body arranged on the floor portion, a covering portion configured to cover the opening portion, and an connecting portion configured to connect the covering portion flexibly to a circumferential portion of the mat main body.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of co-pending application Ser.No. 16/230,846, filed on Dec. 21, 2018, which is a continuationapplication of International Application No. PCT/JP 2017/037980, filedOct. 20, 2017, which claims priority to Japanese Patent Application No.2016/210070, filed Oct. 26, 2016, to Japanese Patent Application No.2016/210071, filed Oct. 26, 2016, to Japanese Patent Application No.2016/210072, filed Oct. 26, 2016, to Japanese Patent Application No.2016/210073, filed Oct. 26, 2016, to Japanese Patent Application No.2016/210074, filed Oct. 26, 2016, and to Japanese Patent Application No.2016/210075, filed Oct. 26, 2016. The contents of these applications areincorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a floor mat provided to a workingmachine such as a backhoe and to the working machine having the floormat.

Description of Related Art

A working machine disclosed in Japanese Unexamined Patent ApplicationPublication No. 2005-222330 is previously known.

The working machine disclosed in Japanese Unexamined Patent ApplicationPublication No. 2005-222330 includes a machine body on which a cabin ismounted, and a floor mat is installed on the boundaries between a floorsurface of the cabin and the side wall surface and between the floorsurface and the front wall surface.

SUMMARY OF THE INVENTION

In an aspect of the present invention, a floor mat arranged in a workingmachine including: a floor portion; a wall portion arranged on acircumferential portion of the floor portion; and an opening portionarranged on a part of a connecting portion of the wall portion, theconnecting portion connecting to the floor portion, is characterized inthat the floor mat includes: a mat main body arranged on the floorportion; a covering portion configured to cover the opening portion; andan connecting portion configured to connect the covering portionflexibly to a circumferential portion of the mat main body, wherein thecovering portion includes: a first cover wall portion having: a sideportion connected to the connecting portion; and a first opposite sideportion and a second opposite side portion each extending from endportions of the side portion and being opposite to each other; a secondcover wall portion extending downward from the first opposite sideportion; and a third cover wall portion extending downward from thesecond opposite side portion, and wherein a length of the second coverwall portion from a portion connecting to the first opposite sideportion to a lower end portion of the second cover wall portion is equalto or less than a thickness of the mat main body, and a length of thethird cover wall portion from a portion connecting to the secondopposite side portion to a lower end portion of the third cover wallportion is equal to or less than the thickness of the mat main body.

DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 is a schematic side view of a working machine;

FIG. 2 is a schematic plan view illustrating a part of the workingmachine;

FIG. 3 is a right side view illustrating a part of the working machine;

FIG. 4 is a perspective view illustrating a part of the working machinein view from a front side;

FIG. 5 is a perspective view illustrating a turn frame and a coveringdevice in view from behind;

FIG. 6 is a perspective view illustrating a cabin in view from below;

FIG. 7 is a perspective view illustrating the turn frame;

FIG. 8 is a right side view illustrating arrangement of a fuel tank andthe like;

FIG. 9 is a perspective view illustrating the fuel tank and the like inview from a right front side;

FIG. 10 is a view illustrating a cross-section of the fuel tank and thelike;

FIG. 11 is a perspective view illustrating the fuel tank and like inview from a left front side;

FIG. 12 is a perspective view illustrating the fuel tank and like inview from a right rear side;

FIG. 13 is a right perspective view illustrating a tank supporting plateand a supporting plate;

FIG. 14 is a left perspective view illustrating a tank supporting plateand a supporting plate;

FIG. 15 is a perspective view illustrating a surrounding structure of anupper portion of an operation fluid tank;

FIG. 16 is a front view illustrating an upper portion of the operationfluid tank;

FIG. 17 is a side view illustrating a state in which a third cover isopened;

FIG. 18 is a front view illustrating a surrounding structure of anoperator seat;

FIG. 19 is a perspective view illustrating a seat base, an insideair/outside air switching device, and an outside-air introducing device;

FIG. 20 is a perspective view illustrating an air conditioning device,the inside air/outside air switching device, and the outside-airintroducing device;

FIG. 21 is a perspective view illustrating the inside air/outside airswitching device;

FIG. 22 is a perspective view illustrating a front portion of the insideair/outside air switching device;

FIG. 23 is an exploded perspective view illustrating the insideair/outside air switching device;

FIG. 24 is a left side view illustrating a state in which a switchingmember is switched;

FIG. 25 is a right side view illustrating a state in which an operationmember of the inside air/outside air switching device is switched;

FIG. 26 is an exploded perspective view illustrating the outside airintroducing device;

FIG. 27A is a front view illustrating a cross section of the outside airintroducing device;

FIG. 27B is a plan view illustrating a cross section of the outside airintroducing device;

FIG. 28 is a perspective view illustrating a traveling frame;

FIG. 29 is a perspective view illustrating a center frame;

FIG. 30A is a plan view illustrating a center portion of the centerframe;

FIG. 30B is an enlarged plan view illustrating the center portion of thecenter frame;

FIG. 31 is a side view illustrating a cross section of the centerportion of the center frame;

FIG. 32 is a front perspective view illustrating a swing bracket;

FIG. 33 is a rear perspective view illustrating the swing bracket;

FIG. 34 is a side view illustrating a cross section of the swingbracket;

FIG. 35 is a perspective view illustrating a state where a hose guide isdetached from the swing bracket;

FIG. 36 is an exploded perspective view illustrating the hose guide;

FIG. 37 is a perspective view illustrating a rear lower portion of acabin in view from below;

FIG. 38 is a perspective view illustrating a bonnet center;

FIG. 39A is a side view illustrating a cross section of the bonnetcenter cut at a position of a second reinforcing portion;

FIG. 39B is a side view illustrating a cross section of the bonnetcenter cut at a position of a first reinforcing portion;

FIG. 40 is a side view illustrating a cross section of a placementportion;

FIG. 41A is a rear view illustrating a cross section of the placementportion cut at a position of the reinforcing portion;

FIG. 41B is a cross-sectional view illustrating another example of thereinforcing portion;

FIG. 42 is a rear view illustrating a cross section of the placementportion cut at a position of an installing portion and a screw insertionportion;

FIG. 43 is an enlarged rear view illustrating the cross section of theplacement portion cut at the position of the installing portion and thescrew insertion portion;

FIG. 44 is a perspective view illustrating a rear bonnet in view fromthe inside;

FIG. 45 is a perspective view illustrating a hinge structure;

FIG. 46 is a plan view illustrating a cross section of the hingestructure;

FIG. 47 is a side view illustrating the hinge structure under a state inwhich the rear bonnet is closed;

FIG. 48 is a side view illustrating the hinge structure under a state inwhich the rear bonnet is opened;

FIG. 49 is a side view illustrating a state in which a lock lever ispulled up with the rear bonnet opened;

FIG. 50 is a perspective view illustrating a state in which a radiatorand an oil cooler are installed;

FIG. 51 is a perspective view illustrating a state in which the oilcooler is fixed to a supporting frame;

FIG. 52 is an exploded perspective view illustrating an installationportion of an upper portion of the oil cooler;

FIG. 53 is an exploded perspective view illustrating an installationportion of a lower portion of the oil cooler;

FIG. 54 is a rear view illustrating a state in which the radiator andthe oil cooler are installed;

FIG. 55 is a rear view illustrating an upper portion of the installationportion of the oil cooler;

FIG. 56 is a perspective view illustrating a floor portion in view froma room of the cabin;

FIG. 57 is a perspective view illustrating a left side of a front lowerframe in view from the room of the cabin;

FIG. 58 is a perspective view illustrating a state in which a floor matis installed;

FIG. 59 is a perspective view illustrating the floor mat;

FIG. 60 is a perspective view illustrating the left side of the frontlower frame with the floor mat installed in view from the room of thecabin;

FIG. 61 is a side cross-sectional view illustrating a state in which afirst front mount is covered with a first covering portion;

FIG. 62 is a perspective view illustrating a left side of a frontportion of the floor mat;

FIG. 63 is a front view illustrating the left side of the front portionof the floor mat;

FIG. 64 is a plan view illustrating the first covering portion under astate before the installation of the floor mat;

FIG. 65A is a cross-sectional view of FIG. 64 in Y1-Y1 arrowed lines;and

FIG. 65B is a cross-sectional view of FIG. 65A in Y2-Y2 arrowed lines.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments of the present invention will be described withreference to the drawings.

First, the overall configuration of the working machine 1 will beschematically described.

FIG. 1 is a schematic side view showing the overall configuration of theworking machine 1 according to the present embodiment. FIG. 2 is aschematic plan view of a part of the working machine 1.

In the present embodiment, a backhoe which is a swiveling workingmachine is exemplified as the working machine 1.

As shown in FIG. 1 , the work machine 1 includes a machine body (a turntable) 2, a traveling device 3, and a work device 4. A cabin 5 ismounted on the machine body 2. An operator seat 6 is provided in theinterior of the cabin 5.

In the explanation of the present embodiment, the front side of theoperator seated on the operator seat 6 of the working machine 1 (thedirection indicated by the arrowed line A1 in FIG. 1 and FIG. 2 ) is thefront, the rear side of the operator (the direction indicated by thearrowed line A2 in FIG. 1 and FIG. 2 ) is the rear, the left side of theoperator (the front surface side of FIG. 1 , the direction indicated bythe arrowed line B1 in FIG. 2 ) is the left, the right side of theoperator (the back surface side of FIG. 1 , the direction indicated bythe arrowed line B2 in FIG. 2 ) is the right.

Further, the horizontal direction which is a direction orthogonal to thefront-rear direction K1 will be described as a machine width directionK2 (refer to FIG. 2 ). The direction from the center portion in thewidth direction of the machine body 2 to the right portion or the leftportion will be described as a machine outward direction. In otherwords, the outer side of the machine body means a direction separatingaway from the center in the machine width direction K2 and in the widthdirection of the machine body 2. In the explanation, the directionopposite to the machine outward direction as a machine inward direction.In other words, the machine inward direction means a directionapproaching the center in the machine width direction K2 and in thewidth direction of the machine body 2.

As shown in FIG. 1 , the traveling device 3 includes a traveling frame 9and a traveling mechanism 10. The traveling mechanism 10 is constitutedof a crawler type traveling mechanism. In other words, the travelingdevice 3 is a crawler type traveling device. The traveling mechanism 10is provided on the left side and the right side of the traveling frame9. Further, the traveling mechanism 10 includes an idler 10A, a drivingwheel 10B, a plurality of rolling wheels 10C, an endless crawler belt10D, and a traveling motor M1 constituted of a hydraulic motor. Theidler 10A is disposed at the front portion of the traveling frame 9, andthe driving wheel 10B is disposed at the rear portion of the travelingframe 9. The plurality of rolling wheels 10C are provided between theidler 10A and the driving wheel 10B. The crawler belt 10D is woundaround the idler 10A, the driving wheel 10B, and the rolling wheel 10C.The traveling motor M1 circulates the crawler belt 10D in thecircumferential direction by driving the drive wheel 10B. A dozer device7 is attached to the front portion of the traveling device 3.

The machine body 2 is turnably supported on a running frame 9 (isconfigured to be turned to the left and the right) about a longitudinalaxis (an axis extending in the vertical direction) by a turning bearing8. The center of the swing bearing 8 is the rotation center of themachine body 2, and the rotation center of this machine body 2 isreferred to as a turn axis X1.

As shown in FIG. 2 , the cabin 5 is mounted to the left of the machinebody 2 and closer to the front portion. An engine E1 is mounted on therear portion of the machine body 2. The engine E1 is disposed on therear portion side of the cabin 5. On the left side of the engine E1, ahydraulic pump P1 is provided. The hydraulic pump P1 is driven by thedriving force of the engine E1. The hydraulic pump P1 outputs theoperation fluid (the hydraulic pressure) for driving a hydraulicactuator such as a hydraulic motor, a hydraulic cylinder, and the likemounted on the working machine 1. In addition, the hydraulic pump P1discharges a pilot pressure for operating a hydraulic valve and ahydraulic pressure for a signal.

As shown in FIG. 2 and FIG. 3 , a fuel tank T1, a battery B1, anoperation fluid tank T2, a radiator R1, and an oil cooler O1 (a heatexchanger) are mounted on the right side (a side) of the cabin 5, thatis, on the right side (a side) of the machine body 2. The fuel tank T1is a tank for storing fuel for the engine E1. The battery B1 is astorage battery that supplies power to the electrical components mountedon the working machine 1. The operation fluid tank T2 is a tank thatstores the operation fluid to be supplied to the hydraulic pump P1. Theradiator R1 cools the coolant of the engine E1. The oil cooler O1 coolsthe operation fluid returning to the operation fluid tank T2.

The fuel tank T1 is disposed at the front portion on the right side ofthe machine body 2. The battery B1 is disposed above the rear portion ofthe fuel tank T1. The operation fluid tank T2 is disposed behind thefuel tank T1 and the battery B1. The radiator R1 and the oil cooler O1are disposed behind the operation fluid tank T2. Further, the radiatorR1 and the oil cooler O1 are arranged side by side (to right side) ofthe engine E1 along the machine width direction K2. The radiator R1 isdisposed closer to the engine E1 than the oil cooler O1. That is, theradiator R1 is disposed on the right side of the engine E1, and the oilcooler O1 is disposed on the right side of the radiator R1. The oilcooler O1 is arranged to face the radiator R1.

A cooling fan configured to be driven by the driving force of the engineE1 is provided between the radiator R1 and the engine E1. The coolingfan is a suction type fan that draws the air from the right side of theoil cooler O1 and supplies to the engine E1 side.

As shown in FIG. 2 , a turning motor M2 constituted of a hydraulic motoris attached to the machine body 2. This turning motor M2 is a motor thatdrives the machine body 2 to rotate about the turn axis X 1. The turningmotor M2 is provided below the cabin 5 and on the lower right side ofthe front portion of the operator seat 6. The turning motor M2 isattached to a turn base plate 56 to be described later. In addition, acontrol valve V1 is provided in the machine body 2. This control valveV1 is a valve unit that aggregates each of the control valves thatcontrol each of the hydraulic actuators equipped in the working machine1.

As shown in FIG. 2 , an exterior cover 21 that covers the engine E1, thehydraulic pump P1, the fuel tank T1, the battery B1, the operation fluidtank T2, the radiator R1, and the oil cooler O1 is mounted on themachine body 2. The exterior cover 21 has a bonnet 22 and a side cover23.

As shown in FIG. 1 and FIG. 2 , the bonnet 22 is a cover mainly coveringthe engine E1. Thus, the bonnet 22 forms an engine room that houses theengine E1. As shown in FIG. 4 and FIG. 5 , the bonnet 22 has a bonnetcenter 24 (a covering member), a rear bonnet 25, a first side bonnet 26,and a second side bonnet 27. The bonnet center 24 is a covering memberthat covers the upper side and the front side of the engine E1. Inaddition, the bonnet center 24 is a covering member for separating theinterior of the cabin 5 from the engine room. The rear bonnet 25 is acovering member that covers the rear of the engine E1. The rear bonnet25 is openable and closable. The first side bonnet 26 is a coveringmember that covers the engine E1 and the left side of the hydraulicpump. The second side bonnet 27 is a covering member that covers theright side of the engine E1, the radiator R1, and the oil cooler O1. Inthe second side bonnet 27, an opening for taking the air into the engineroom (the bonnet 22) is formed.

As shown in FIG. 2 , the side cover 23 is located on the right side ofthe cabin 5 and covers the fuel tank T1, the battery B1, and theoperation fluid tank T2. As shown in FIG. 2 , FIG. 3 , and FIG. 5 , theside cover 23 includes a first cover 28, a second cover 29, and a thirdcover 30. The first cover 28 is a covering member that covers the leftsides of the fuel tank T1, the battery B1, and the operation fluid tankT2. The second cover 29 is a covering member that covers the right sidesof the fuel tank T1, the battery B1, and the operation fluid tank T2.The third cover 30 is a covering member that covers the upper sides andthe front sides of the fuel tank T1, the battery B1, and the operationfluid tank T2. The third cover 30 is openable and closable, and when thethird cover 30 is opened, the upper portions of the fuel tank T1, thebattery B1, and the operation fluid tank T2 are opened.

As shown in FIG. 4 , the operator seat 6 is provided in front of thebonnet center 24. Below the operator seat 6, a seat base 31 forsupporting the operator seat 6 is provided. A floor portion (a step) 419is disposed in front of the seat base 31, and a floor mat 32 is laid onthe floor portion 419. An air conditioning device 37 for adjusting theair in the room of the cabin 5 is provided inside the seat base 31. Inthis embodiment, the air conditioning device 37 is a heating device.Meanwhile, it should be noted that the air conditioning device may be adevice having only a cooling function or may be a device having both theheating function and the cooling mechanism. On the left side of theoperator seat 6, an operation device 33L is provided. On the right sideof the operator seat 6, an operation device 33R is provided. Theoperation devices 33L and 33R are devices for steering the workingdevice 4, the dozer device 7, and the like. In front of the operatorseat 6, there are provided a traveling lever 34 for operating thetraveling device 3, a first operation pedal 35 for swinging the swingbracket 14, which will be described later, and a second operation pedal36 for operation a working tool mounted instead of a bucket 17A.

As shown in FIG. 6 , the cabin 5 includes a first side surface portion38 on the left side, a second side surface portion 39 on the right side,a front surface portion 40 provided between the front ends of the firstside surface portion 38 and the second side surface portion 39, a backsurface portion 41 provided between the rear ends of the first side faceportion 38 and the second side face portion 39, a roof 42 (refer to FIG.1 ) provided between the upper ends of the first side face portion 38and the second side face portion 39. The lower surface of the cabin 5 isopened downward. The cabin 5 is mounted on the machine body 2 so as tocover the operator seat 6, the control devices 33L and 33R, the floormat 32, the travel lever 34, the first operation pedal 35, the secondoperation pedal 36, and the like.

A door 43 and a side window 44 are provided on the first side faceportion 38. An opening/closing window 45 is provided on the upperportion of the second side face portion 39. An outside air introductionport 46 for introducing the outdoor air (referred to as the outside air)of the cabin 5 is provided in a lower portion of the second side faceportion 39. In the following description, the air in the room of thecabin 5 is referred to as inside air.

The front surface portion 40 is provided with a front windshield, andthe back surface portion 41 is provided with a rear windshield 47.

The first front pillar portion 77 is provided at a corner portionbetween the front surface portion 40 and the first side surface portion38. At the corner portion between the front surface portion 40 and thesecond side surface portion 39, the second front pillar portion 78 isprovided. The first front pillar portion 77 and the second front pillarportion 78 are provided being spaced apart from each other in themachine width direction K2. The first rear pillar portion 79 is providedat a corner portion between the back surface portion 41 and the firstside surface portion 38. A second rear pillar portion 80 is provided ata corner portion between the back surface portion 41 and the second sidesurface portion 39. The first rear pillar portion 79 and the second rearpillar portion 80 are provided being spaced apart from each other in themachine width direction K2.

A front lower frame 52 is provided at the lower end portion of the frontportion of the cabin 5. The front lower frame 52 is provided between thelower end portions of the first front pillar portion 77 and the secondfront pillar portion 78. A front mount member (a first front mountmember 48, a second front mount member 49) is provided in the frontlower frame 52. The first front mount 48 is assembled to the left endportion of the front lower frame 52. The second front mount 49 isassembled to the right end portion of the front lower frame 52. Thefirst front mount 48 and the second front mount 49 have vibration proofrubbers, and support the front portion of the cabin 5 with respect tothe machine body 2 so as to prevent the vibration.

A rear lower frame 53 is provided at the lower end portion of the rearportion of the cabin 5. The rear lower frame 53 is provided between thelower end portions of the first rear pillar portion 79 and the secondrear pillar portion 80. In addition, the rear lower frame 53 is providedat a position higher than the front lower frame 52. A rear mount member(a first rear mount member 50, a second rear mount member 51) isprovided in the rear lower frame 53. The first rear mount 50 isassembled to the left end portion of the rear lower frame 53. The secondrear mount 51 is assembled to the right end portion of the rear lowerframe 53. The first rear mount 50 and the second rear mount 51 havevibration proof rubbers, and are parts for supporting the rear portionof the cabin 5 with respect to the machine body 2 to prevent thevibration.

As shown in FIG. 3 , FIG. 5 , and FIG. 7 , the machine body 2 has a turnframe 54 as a skeleton and a weight 55 attached to a rear portion of theturn frame 54.

The turn frame 54 has a turn base plate (a base plate) 56, a pluralityof vertical ribs (a first vertical rib 57L, a second vertical rib 57R),a support bracket 58, a partition plate 59, and a support frame 60. Inaddition, the turn frame 54 is provided with a bracket, a stay, and thelike for attaching equipment, tanks, other parts, and the like which aremounted on the machine body 2.

As shown in FIG. 7 , the turn base plate 56 is formed of a thick steelplate or the like, and constitutes the bottom portion of the machinebody 2. As shown in FIG. 1 , the turn base plate 56 is supported on thetraveling device 3 so as to be rotatable around the turn axis X1 via theturn bearing 8.

The first vertical rib 57L and the second vertical rib 57R are membersthat reinforce the turn base plate 56, and are provided extending fromthe front portion to the rear portion of the turn base plate 56. Thefirst vertical ribs 57L and the second vertical ribs 57R are erected onthe turn base plate 56, and juxtaposed at intervals in the machine widthdirection K2. The first vertical rib 57L is located to the left of thesecond vertical rib 57R.

The support bracket 58 is provided at the front portions of the firstvertical rib 57L and the second vertical rib 57R. The support bracket 58and the front portions of the first vertical rib 57L and the secondvertical rib 57R are provided at positions deviated rightward from thecenter of the turn base plate 56 in the machine width direction K2. Thesupport bracket 58 has a first support portion 61A and a second supportportion 61B positioned below the first support portion 61A at the frontportion. In addition, the support bracket 58 has, at the rear portion, aleft coupling portion 62L and a right coupling portion 62R located onthe right side of the left coupling portion 62L. The left couplingportion 62L is coupled to the front portion of the first vertical rib57L. The right coupling portion 62R is coupled to the front portion ofthe second vertical rib 57R. The support bracket 58 is provided with athrough hole 63 extending from a portion between the left couplingportion 62L and the right coupling portion 62R toward a portion betweenthe first supporting portion 61A and the second supporting portion 61B.The through hole 63 is a passage formed penetrating through the membersconstituting the support bracket 58 in the front-rear direction. In thethrough hole 63, a hydraulic hose or the like is inserted from themachine body 2 side (a rear side) toward the front.

As shown in FIG. 1 , a swing bracket 14 is attached to the supportbracket 58 so as to be swingable around a vertical axis (an axisextending in the vertical direction). A working device 4 is attached tothe swing bracket 14.

As shown in FIG. 7 , the partition plate 59 is a member for partitioningthe front lower portion of the engine room, and is provided along themachine width direction K2. In addition, the partition plate 59 iserected on the turn base plate 56. The lower part of the bonnet center24 is attached to the upper part of this partition plate 59. Inaddition, the operator seat 6 is provided forward from the partitionplate 59.

As shown in FIG. 7 , the support frame 60 is erected on a rear portionof the turn base plate 56 behind the partition plate 59. The supportframe 60 is arranged in the bonnet 22 (an engine room), and supports thebonnet 22 and the peripheral components of the engine E1. The supportframe 60 includes a plurality of leg members (a first leg 64, a secondleg 65, and a third leg 66) standing on the turn base plate 56, and beammembers 67 (supporting portions) fixed to the upper portion of theplurality of leg members. Each of the first leg 64, the second leg 65,the third leg 66 and the beam member 67 is formed of a plate material.

The first leg 64 includes a first pillar portion 64A, a first horizontalportion 64B, and a hanging portion 64C. The first pillar portion 64Astands upright on the front left side of the engine room. The firsthorizontal portion 64B extends rearward from the upper end of the firstpillar portion 64A. The hanging portion 64C extends downward from therear end of the first horizontal portion 64B.

The second leg 65 has a second support post 65A and a second horizontalportion 65B. The second support post 65A stands upright on the center ofrear portion of the engine room in the machine width direction K2. Thesecond horizontal portion 65B extends forward from the upper end of thesecond support post 65A.

The third leg 66 has a third pillar portion 66A and a third horizontalsection 66B. The third pillar portion 66A stands upright on the frontright portion of the engine room. The third horizontal portion 66Bextends rearward from the upper end of the third pillar portion 66A.

The beam member 67 is placed over the first horizontal portion 64B, thesecond horizontal portion 65B, and the third horizontal portion 66B sothat the plate surface thereof faces upward and downward, and is fixedto these horizontal portions. A first thread hole 68 is formed in theleft side portion of the beam member 67.

The threaded hole is a portion in which a female thread is cut on acolumnar inner circumferential surface formed in a penetrated orbottomed shape in the beam member 67. This also applies to the followingdescription.

In addition, a second thread hole 69 is formed in the right side portionof the beam member 67. A third threaded hole 70 is formed on the machineinward side of the first thread hole 68, and a fourth threaded hole 71is formed on the machine inward side of the second threaded hole 69.

The first thread hole 68 is a thread hole for attaching the first rearmount 50. The second thread hole 69 is a thread hole for attaching thesecond rear mount 51. Thus, the lower end portion (the rear lower frame53) of the rear portion of the cabin 5 is attached to the beam member 67(the support frame 60) via the first rear mount 50 and the second rearmount 51. The beam member 67 is a support member for supporting the rearportion of the cabin 5.

The third thread hole 70 and the fourth thread hole 71 are thread holesfor attaching the upper part of the bonnet center 24.

As shown in FIG. 4 , on the left side of the front portion of themachine body 2, a first mount attachment portion 72 for attaching thefirst front mount 48 is provided. On the right side of the front portionof the machine body 2, a second mount attachment portion 73 forattaching the second front mount 49 is provided. Thus, the lower endportion (the front lower frame 52) of the front portion of the cabin 5is attached to the first mount attachment portion 72 via the first frontmount 48, and is attached to the second mount attachment portion 73 viathe second front mount 49.

As shown in FIG. 3 and FIG. 5 , the weight 55 forms the left side lowersurface, the right side lower surface, and the rear side lower surfaceof the engine room. As shown in FIG. 1 and FIG. 5 , the left sidesurface of the turn frame 54, that is, the front side of the weight 55is covered with a left turning cover 74. As shown in FIG. 3 , the rightside surface of the turn frame 54, that is, the front side of the weight55 is covered with the right turn cover 75. As shown in FIG. 4 , thefront side of the turn frame 54 is covered with the front turn cover 76.The front side of the seat base 31, that is, the upper side of the turnframe 54 is covered with a floor part (a step) that supports the floormat 32.

As shown in FIG. 1 , the working device 4 has a boom 15, an arm 16, anda bucket (work implement) 17. The base portion of the boom 15 ispivotally attached to the swing bracket 14 so as to be rotatable about ahorizontal axis (an axis extending in the machine width direction K2).Thereby, the boom 15 is freely swingable in the vertical direction. Thearm 16 is pivotally attached to the distal end side of the boom 15 so asto be rotatable about a transverse axis. As a result, the arm 16 canfreely swing back and forth or up and down. The bucket 17 is provided onthe distal end side of the arm 16 so as to perform a squeeze operationand a dump operation. Instead of or in addition to the bucket 17, it ispossible for the working machine 1 to mount another working tool(hydraulic attachment) which can be driven by a hydraulic actuator.Examples of other work tools include a hydraulic breaker, a hydrauliccrusher, an angle bloom, a ground auger, a pallet fork, a sweeper, amoor, and a snow blower.

The swing bracket 14 is swingable by expansion and contraction of aswing cylinder C2 (see FIG. 7 ) provided on the right side of themachine body 2. The boom 15 is swingable by expansion and contraction ofthe boom cylinder C3. The arm 16 is swingable by expansion andcontraction of the arm cylinder C4. The bucket 17 is freely squeezableand dumpable by expansion and contraction of the bucket cylinder (workimplement cylinder) C5. The swing cylinder C2, the boom cylinder C3, thearm cylinder C4, and the bucket cylinder C5 are constituted of hydrauliccylinders (hydraulic actuators).

Next, the supporting structure of the fuel tank T1 will be described.

As shown in FIG. 8 , the fuel tank T1 has a tank main body T11 and anextension portion T12. The fuel tank T1 is a resin product of a hollowstructure formed by blow molding, rotational molding or the like. Thus,the tank main body T11 and the extension portion T12 communicate witheach other, and the fuel is stored in the tank main body T11 and theextension portion T12.

On the rear side of the upper part of the tank main body T11, a recess91 is provided. The recessed portion 91 is formed by recessing the rearside of the upper portion of the tank main body T11 downward withrespect to the front portion. A battery B1 is arranged in the recess 91.On the contrary, the front part of the upper part of the tank main bodyT11 projects upward with respect to the rear part. A fuel filler opening93 which is opened and closed by a fuel cap 94 is provided on the uppersurface of the projecting portion 92 projecting upward.

As shown in FIG. 9 to FIG. 11 , the tank main body T11 is supported by atank support plate 95 attached to the machine body 2. The tank supportplate 95 is provided spaced apart upward from the turn base plate 56.That is, the tank main body T11 is supported on the tank support plate95 in a state of being spaced upward from the machine body 2 (swivelboard 56). A swing cylinder C2 is inserted through the space between thetank main body T11 and the turn base plate 56 (see FIG. 8 ). Further,the tank support plate 95 is disposed on one side (inside the airframebody) of the tank main body T11 (fuel tank T1). Specifically, the tanksupport plate 95 is disposed on the left side of the tank main body T11.

As shown in FIG. 13 and FIG. 14 , the tank support plate 95 includes aside plate portion 96, a bottom plate portion 97, a attaching plateportion 98, a plurality of reinforcing plates (a first reinforcing plate99A, a second reinforcing plate 99B). The side plate portion 96, thebottom plate portion 97, and the attachment plate portion 98 areintegrally formed by bending a sheet material. The side plate portion 96is a long plate in the front-rear direction K1, and is provided in avertical direction in which the plate surface faces the machine widthdirection K2. Further, the side plate portion 96 is formed to have alength extending from the front portion to the rear portion of the tankmain body T11 (see FIG. 11 ). Further, the side plate portion 96 isdisposed on the inner side of the body (one side) of the lower portionof the tank main body T11 (see FIG. 10 ).

As shown in FIG. 13 and FIG. 14 , the bottom plate portion 97 extendsfrom the lower end of the side plate portion 96 to the machine outwarddirection (the side of the tank main body T11) and receives one sideportion (the left side portion) of the tank main body T11.

More specifically, the bottom plate portion 97 has a first receivingportion 100 and a second receiving portion 101. The first receivingportion 100 is a portion extending from the lower end of the side plateportion 96 and is provided from the front portion to the rear portion ofthe side plate portion 96. A bottom portion of one side portion (leftside portion) of the tank main body T11 is placed on the first receivingportion 100 (see FIG. 10 ). That is, the first receiving portion 100receives one side portion (the side portion on the inboard side of thebody) of the tank main body T11 from the front portion to the rearportion.

The second receiving portion 101 extends from the rear portion of thefirst receiving portion 100 to the machine outward direction, and therear portion of the bottom portion 102 of the tank main body T11 isplaced on the second receiving portion 101. That is, the secondreceiving portion 101 receives the rear portion of the tank main bodyT11. As shown in FIG. 12 , the second receiving portion 101 is placed onthe placing brackets 103A and 103B (see FIG. 7 and FIG. 12 ) provided inthe turn frame 54. As shown in FIG. 7 and FIG. 12 , a support base 436for supporting the operation fluid tank T2 is fixed on the turn baseplate 56 by welding, and placing the brackets 103A and 103B are mountedon part of the support base 436. As shown in FIG. 14 , a bent portion104 extending downward is provided at the rear end portion of the bottomplate portion 97 by bending a plate material forming the tank supportplate 95. Thereby, the strength of the bottom plate portion 97 isimproved.

The bottom portion 102 of the tank main body T11 is placed on the firstreceiving portion 100 and the second receiving portion 101 via anelastic plate (rubber plate).

As shown in FIG. 13 and FIG. 14 , the attaching plate portion 98 extendsfrom the side plate portion 96 to the side opposite to the tank mainbody T11 side. More specifically, the attaching plate portion 98 extendsfrom the upper end of the side plate portion 96 toward the machineinward direction. The attachment plate portion 98 is provided from thefront portion to the rear portion of the side plate portion 96. As shownin FIG. 11 , the front portion of the side plate portion 96 is fixed toa mounting boss 106 (see FIG. 7 ) provided on the right side of theupper surface of the support bracket 58 with bolts. The rear portion ofthe side plate portion 96 is fixed to a support stay 107 (see FIG. 7 )provided on the turn frame 54 by bolts.

As shown in FIG. 7 , the support stay 107 is fixed by welding to a partof a support stand 436 that supports the operation fluid tank T2.

As shown in FIG. 14 , the first reinforcing plate 99A is provided at afront portion between the side plate portion 96 and the attaching plateportion 98 and welded to the side plate portion 96 and the attachingplate portion 98. The second reinforcing plate 99B is provided at a rearportion between the side plate portion 96 and the attaching plateportion 98 and is welded to the side plate portion 96 and the attachingplate portion 98.

As shown in FIG. 8 , FIG. 9 , and FIG. 10 , the extended portion T12extends downward from the tank main body T11 and is supported by themachine body 2. In the present embodiment, the extension part T12 ismounted on the turn base plate 56 via an elastic plate 108 (rubberplate), and is supported by the turn base plate 56. Note that theextended portion T12 may be in directly contact with the pivot substrate56. Further, a placing bracket made of a plate material, a blockmaterial or the like may be fixed to the turn base plate 56, and theextension part T12 may be placed directly or via an elastic plate on theplacing bracket.

The extension portion T12 extends downward from a side portion of thetank main body T11 on the outer side of the body. In other words, itextends from the other side which is the side opposite to the one sidewhich is the side portion of the tank main body T11 on the side wherethe tank support plate 95 is arranged. Further, the extension portionT12 is provided in the front portion of the tank main body T11. Further,the extended portion T12 is located on the outer side of the swingcylinder C2 (on the right side). A suction pipe 109 and a drain pipe 110positioned below the suction pipe 109 are provided on the lower part ofthe rear side of the extension part T12 (see FIG. 8 ). The suction pipe109 is a pipe for discharging the fuel in the fuel tank T1 for sendingfuel to the engine E1, and the drain pipe 110 is a pipe for dischargingfluid when removing the fuel in the fuel tank T1.

As shown in FIG. 10 and FIG. 11 , a support plate 111 is arranged on theoutside of the body (one side) of the tank main body T11. The lowerportion of the support plate 111 is disposed between the tank main bodyT11 and the side plate portion 96, and is fixed to the side plateportion 96. The tank main body T11 is brought into contact with thesupport plate 111 via the elastic plate. The support plate 111 isdisposed inside the first cover 28 of the side cover 23. The frontportion of the first cover 28 is fixed to the front portion of thesupport plate 111 by bolts. A battery bracket 112 for supporting thebattery B1 is attached to an upper portion of the support plate 111. Thebattery bracket 112 is also attached to the operation fluid tank T2 (seeFIG. 8 ).

As shown in FIG. 13 , a band hanging plate 113 is provided at the frontportion of the support plate 111. The band hanging plate 113 is formedintegrally with the support plate 111 by bending a part of a platematerial forming the support plate 111. Thus, the support plate 111 andthe band hanging plate 113 are formed of a single plate material. Theband hanging plate 113 includes a main body plate 113 a, a reinforcingplate 113 b, and an extension plate 113 c. The main body plate 113 aextends from the lower front end of the support plate 111 to the machineoutward direction. The main body plate 113 a has a long groove 113 d anda hooking portion 113 e on the outer side of the body. The elongatedgroove 113 d is formed by a vertically elongated edge formed through themain body plate 113 a, and the hooking portion 113 e is a portionpositioned on the outer side of the long groove 113 d on the airframebody. Further, the upper end of the main body plate 113 a is formed inan inclined shape which moves downward as going outward of the machinebody.

The reinforcing plate 113 b extends from the upper front end of thesupport plate 111 to the machine outward direction. The reinforcingplate 113 b is formed narrower than the main body plate 113 a.

The extension plate 113 c extends downward from the main body plate 113a. That is, the extension plate 113 c extends downward from the lowerend of the support plate 111. The side plate portion 96 and the bottomplate portion 97 protrude forward from the extension plate 113 c. Theextension plate 113 c has a first end portion 114 which is in contactwith the side plate portion 96 and a second end portion 115 which is incontact with the bottom plate portion 97. The first end portion 114 iswelded to the side plate portion 96. The second end portion 115 iswelded to the bottom plate portion 97.

As shown in FIG. 8 and FIG. 9 , the fuel tank T1 is pressed against thesupport plate 111 by the fixing band 116 and fixed thereto. At one endof the fixing band 116, a hook portion 116 a is provided. The hookportion 116 a is hooked on the hooking portion 113 e of the band hangingplate 113. In other words, the fixing band 116 is hooked on the bandhanging plate 113. At the other end of the fixing band 116, a fixingbolt 117 is provided. The fixing bolt 117 is fixed to the stay 118 fixedto the lower part of the right side surface of the operation fluid tankT2 via the nut 119.

Next, the peripheral structure of the upper part of the operation fluidtank T2 will be described.

As shown in FIG. 8 , FIG. 15 , and FIG. 16 , the height of the uppersurface of the operation fluid tank T2 is substantially the same heightposition as the upper surface of the battery B1 (a position slightlyhigher than the upper surface of the battery B1). On the upper surfaceof the operation fluid tank T2, an fuel supply cap 121 for closing thefuel supply port 120 and the fuel supply port 120 is provided. The fuelsupply cap 121 is provided with a plurality of tool engaging portions122. The plurality of tool engaging portions 122 are provided at fourpositions on the outer circumferential portion of the upper surface ofthe fueling cap 121 at intervals of 90° in the circumferentialdirection. Disconnector 123 (first electrical component) is provided ata position that does not obstruct insertion of a tool into at least onetool engaging portion 122 in front of this fueling cap 121 (a positionnot overlapping the tool engaging portion 122 when viewed from thefront). The disconnector 123 is, for example, a battery disconnectorswitch for cutting off the supply current of the battery B1 at abnormaltimes, emergencies, maintenance, and the like.

As shown in FIG. 16 , the disconnector 123 is fixed to a first attachingbracket (attaching bracket) 124 fixed to the upper surface of theoperation fluid tank T2. The first attaching bracket 124 is formed of athin plate material. The first attaching bracket 124 has a lower wallportion 124 a, a vertical wall portion 124 b, and a attaching wallportion 124 c. The lower wall portion 124 a, the vertical wall portion124 b, and the attachment wall portion 124 c are formed by bending asheet material. The lower wall portion 124 a is disposed in front of aside portion on the inner side of the body of the fuel supply cap 121and is fixed to the upper surface of the operation fluid tank T2 bywelding. The vertical wall portion 124 b extends upward from the endportion on the inner side of the body of the lower wall portion 124 a.Further, the vertical wall portion 124 b extends in an inclineddirection that moves toward the inside of the body as it goes upwardfrom the bottom wall portion 124 a. The attaching wall portion 124 cextends upward from the vertical wall portion 124 b. The disconnector123 is attached to the attaching wall portion 124 c via the mountingplate 125. That is, the lower portion of the mounting plate 125 is fixedto the attaching wall portion 124 c by bolts and nuts. The disconnector123 is fixed to the upper portion of the mounting plate 125 by bolts andnuts. It should be noted that the disconnector 123 may be directly fixedto the attaching wall portion 124 c with a bolt.

As shown in FIG. 15 , the slow blow fuse 126 (second electricalcomponent) and the fuel buzzer 127 (second electrical component) areprovided on the front side of the fuel supply cap 121 and thedisconnector 123 (the first electrical component) are arranged. The slowblow fuse 126 is a fuse having a property of breaking when a largecurrent continuously flows without being cut off by an instantaneouscurrent. The fuel buzzer 127 is a buzzer for informing that the fuel hasbecome full when refueling the fuel tank T1.

According to the above configuration, since there are no obstructiveparts, members, and the like. in front of the fuel supply cap 121, thefuel supply cap 121 can be accessed from the front side. That is, byengaging the tool from the front side with the tool engaging portion 122of the fuel supply cap 121, the fuel supply cap 121 can be opened andclosed by loosening or tightening the fuel supply cap 121 with respectto the fuel filler port 120.

As shown in FIG. 11 and FIG. 15 , the slow blow fuse 126 and the fuelbuzzer 127 are attached to the second attaching bracket (attachingbracket) 128 attached to the battery bracket 112. The second attachingbracket 128 is disposed on the inner side of the body of the battery B1,and the lower end side thereof is fixed to the inner side of the body ofthe battery bracket 112.

FIG. 17 is a side view of the second cover 29 viewed from the right sidein a state where the third cover 30 is opened. As shown in FIG. 17 , thetool engaging portion 122 is positioned lower than the edge portion 29 aof the upper end of the second cover 29, and the fuel supply cap 121 andthe oil supply port 120 from the upper surface of the operation fluidtank T2. The height is suppressed to a minimum height that can form ascrew thread for attaching to the fuel filler cap 121 in the fuel fillerport 120. Thereby, the manufacturing cost of the operation fluid tank T2having the fuel filler port 120 can be suppressed.

In the present embodiment, the working machine 1 includes the machinebody 2, the fuel tank T1, a tank support plate 95 that is disposed onone side of the fuel tank T1 and attached to the machine body 2, and thefuel tank T1 has a tank main body T11 supported on the tank supportplate 95 in a state of being spaced apart upward from the machine body 2and an extended portion T12 extending downward from the other sideportion which is the side opposite to one side portion of the tank mainbody T11 and supported by the machine body 2. That is, the fuel tank T1is supported by the tank support plate 95 with respect to the machinebody 2 and also supported by the extended portion T12. As a result, asufficient supporting force for supporting the fuel tank T1 can besecured. Further, since the supporting force of the fuel tank T1 can besufficiently secured, even when the capacity of the fuel tank T1 and theself-weight of the tank increase, it is possible to prevent the tanksupport plate 95 from being deformed due to insufficient strength.

The tank support plate 95 includes a side plate portion 96 disposed onthe side of one side of the tank main body T11, a bottom plate portion97 extending from the lower portion of the side plate portion 96 towardthe tank main body T11 and supporting one side portion of the tank mainbody T11, and a attaching plate portion 98 extending from the upperportion of the side plate portion 96 on the side opposite to the side ofthe tank main body T11 and attached to the machine body 2. That is, bysupporting one side portion of the tank main body T11 via the side plateportion 96, the bottom plate portion 97 and the attaching plate portion98 of the tank supporting plate 95 and supporting the other side portionof the tank main body T11 with the extension portion T12, it is possibleto support the fuel tank T1 with support at both ends, and it ispossible to sufficiently ensure the supporting force of the fuel tankT1.

The bottom plate portion 97 has a first receiving portion 100 forsupporting one side portion of the tank main body T11 and a secondreceiving portion 100 extending from the rear portion of the firstreceiving portion 100 on the opposite side to the side plate portion 96,and a second receiving portion 101 for supporting the first receivingportion 101. Thereby, the tank main body T11 can be supported over awide range.

Also, the support plate 111, which is arranged on one side of the tankmain body T11 and the lower part thereof is fixed to the side plate part96 of the tank support plate 95, and the tank main body T11 is pressedagainst and fixed to the support plate 111 and a band hanging plate 113which is formed by bending a plate material forming the support plate111 and to which one end portion of the fixing band 116 is latched. Inthis manner, by forming the band hanging plate 113 by folding a part ofthe plate material forming the support plate 111, the strength of theband hanging plate 113 can be secured. As a result, the strength of theband hanging plate 113 can be improved as compared with the case wherethe band hanging plate 113 is attached to the support plate 111 bywelding or the like.

The band hanging plate 113 extends from the support plate 111 toward theother side portion of the tank main body T11 and has an extension plate113 c extending downward from the lower end of the support plate 111 atthe lower portion, the extension plate 113 c has a first end portion 114welded to the side plate portion 96 and a second end portion 115 weldedto the bottom plate portion 97. That is, by welding the first endportion 114 of the extension plate 113 c of the band hanging plate 113formed by bending the plate material to the side plate portion 96 andwelding the second end portion 115 to the bottom plate portion 97, thestrength of the tank support the plate 95 can be improved. In addition,the tank supporting force of the bottom plate portion 97 is improved. Inaddition, the strength of the band hanging plate 113 is improved. Byincreasing the strength of the tank supporting plate 95 and the bandhanging plate 113, it is possible to cope with the increase in thecapacity and weight of the fuel tank T1.

In addition, an operation fluid tank T2 to which the fuel supply cap 121having the tool engagement portion 122 is detachably attached, anattaching bracket 124 (first attaching bracket) fixed to the uppersurface of the operation fluid tank T2, and a first electrical component(disconnector 123) attached to the attaching bracket 124. The attachingbracket 124 has a lower wall portion 124 a fixed to the upper surface ofthe operation fluid tank T2, a vertical wall portion 124 b extending inthe inclined direction to be shifted to the machine inward direction asgoing upward from the lower wall portion 124 a, and a attaching wallportion 124 c to which the first electrical component is attached,extending upward from the vertical wall portion 124 b. The firstelectrical component and the attaching bracket 124 are disposed forwardof the axial center of the fuel supply cap 121 and on the inner side inthe machine width direction with respect to the tool engaging portion122. That is, by arranging the first electrical component at a positionthat does not obstruct insertion of the tool into the tool engagingportion 122, an access route for accessing the fuel supply cap 121 fromthe front side can be secured. Conventionally, since the attachingbracket for supporting the first electrical component is suspended fromthe first electrical component and fixed to the upper surface of theoperation fluid tank, the attaching bracket may interfere with thewiring of the harness or the like in some cases. On the other hand, inthe present embodiment, the attaching bracket is provided with thevertical wall portion 124 b that extends in the inclined direction thatmoves inward in the machine width direction as going upward from thelower wall portion 124 a toward the attaching wall portion 124 c. As aresult, it is possible to secure a routing path (wiring path) of adistribution member (wiring member) such as a harness on the lower sideof the first electrical component.

A battery B1 disposed in front of the operation fluid tank T2 and at aposition where the height of the upper surface is lower than the toolengaging portion 122, a second attaching bracket disposed on the innerside in the machine width direction of the battery B1 which is attachedto the second attaching bracket 128 and is disposed in front of thefirst electrical component (disconnector 123) and on the inner side inthe machine width direction of the battery B1 (the slow blow fuse 126, afuel buzzer 127). That is, by placing the second electrical component onthe inner side of the body of the battery B1, it is possible to securean access route for accessing the fuel supply cap 121 from the frontside.

Conventionally, slow blow fuses and fuel buzzers are assembled on theattaching bracket at the front side of the oil supply cap, and the slowblow fuse, the fuel buzzer and the attaching bracket become obstructivefor accessing the fuel supply cap from the front side. Thus,conventionally, it has been done from the right side to engage the toolto the tool engaging portion of the fuel filler cap. In order to relaxor tighten the filler cap from the right, the tool engaging portion mustprotrude above the edge of the upper end of the second cover. Thus, itis necessary to increase the height of the fuel supply cap and thefiller opening, which leads to weight increase and high cost.

In the present embodiment, since the fuel supply cap 121 can be accessedfrom the front, it is not necessary to adjust the heights of the fuelsupply cap 121 and the fuel supply port 120 to the height of the secondcover 29, so that the positions of the fuel supply cap 121 and the fuelsupply port 120. It is possible to suppress the height to the minimumheight. As a result, weight and cost can be reduced.

Further, in the present embodiment, since the slow blow fuse 126 and thefuel buzzer 127 are attached to the second attaching bracket 128 whichis a mounting member different from the first attaching bracket 124, theshape of the first attaching bracket 124 is simplified. In addition, thedimension of the first attaching bracket 124 in the machine widthdirection K2 is also reduced. This makes it easy to arrange wiringmembers such as harnesses (wired) arranged (arranged) in the vicinity ofthe first bracket.

Next, the inside/outside air switching device 136 selectivelyintroducing the inside air and the outside air into the air conditioningdevice 37 and the outside air introduction device 137 introducing theoutside air into the inside/outside air switching device 136 will bedescribed.

As shown in FIG. 18 and FIG. 19 , the seat base 31 for supporting theoperator seat 6 includes a seat supporting frame 138 and anopening/closing cover 139 for covering the front side (one side) of theseat supporting frame 138 so as to freely open and close. The sheetsupport frame 138 includes an upper plate 140, a lower plate 141disposed below and spaced apart from the upper plate 140, a plurality ofconnecting frame members (first frame members 142A, a second framemember 142B, a third frame member 142C, a fourth frame member 142D). Theseat supporting frame 138 has a space between the upper plate 140 andthe lower plate 141 in which the air conditioning device 37, otherequipment, parts, and the like can be placed. That is, the airconditioning device 37 and the like can be accommodated in the seatsupporting frame 138.

The upper plate 140 has a seat attachment portion 140 a to which theoperator seat 6 is attached, a first attachment portion 140 b to whichthe left-hand operation device 33L is attached, and a second attachmentportion 140 c to which the right-hand operation device 33R is attached.The seat attachment portion 140 a is provided at the center portion ofthe upper plate 140 in the machine width direction K2. The firstattachment portion 140 b is provided on the left side portion of theupper plate 140. The second attachment portion 140 c is provided on theright side portion of the upper plate 140. On the front surface of theupper plate 140, a first vibration isolating material 143 positioned onthe left side of the seat attachment portion 140 a and a secondvibration isolating material 144 positioned on the right side of theseat attachment portion 140 a are provided.

The first frame member 142A supports the left end portion and the rearend portion of the first attachment portion 140 b. The second framemember 142B supports the right front portion of the first attachmentportion 140 b. The third frame member 142C supports the left frontportion of the second attachment portion 140 c. The fourth frame member142D supports the left and right rear portions of the second attachmentportion 140 c and the front-rear middle portion of the second attachmentportion 140 c.

The opening and closing cover 139 is formed of a plate material and isformed to have a lateral width extending from one end to the other endin the body width direction K2 of the seat supporting frame 138. Acutout portion 146 for inserting the air supply duct 145 from the seatsupport frame 138 is formed on an upper right portion of the open/closecover 139. The air supply duct 145 is a duct for guiding conditioned airsent from the air conditioning device 37, and is connected to a blower147 provided at the front of the right operation device 33R.

The opening and closing cover 139 is pivotally supported by a firsthinge 148A and a second hinge 148B so as to be rotatable about atransverse axis. The first hinge 148A is provided at the lower endportion of the second frame member 142B. The second hinge 148B isprovided at the lower end portion of the third frame member 142C. Thus,the opening and closing cover 139 is vertically swingably connected tothe seat supporting frame 138 by the first hinge 148A and the secondhinge 148B so as to freely open and close by rocking up and down.

Further, the open/close cover 139 has a lock member 149, a first openinggroove 150, and a second opening groove 151. The locking member 149 isprovided at the upper portion of the central portion of theopening/closing cover 139. The locking member 149 is a componentoperated by a key and locks in a state in which the opening and closingcover 139 is closed by engaging with an engaging groove (not shown)provided in the upper plate 140. Thus, when the lock of the lock member149 is released by the key operation, the openable cover 139 can beopened without a tool. The opening and closing cover 139 is pressedagainst the first vibration-proofing material 143 and the secondvibration-proofing material 144 in a closed state, andvibration-proofed.

The first opening groove 150 is formed by a rectangular shaped laterallyelongated groove formed through the opening and closing cover 139. Thefirst opening groove 150 is provided in the upper and lower middleportions of the opening and closing cover 139 below the operator seat 6.The second opening groove 151 is formed by a rectangular shapedvertically elongated groove formed through the opening and closing cover139. The second opening groove 151 is provided in a lower portion on theright side of the opening/closing cover 139.

An air conditioning device 37 is provided in the seat support frame 138and on the left side between the seat attachment portion 140 a and thelower plate 141. That is, the seat support frame 138 is a member thathouses the air conditioning device 37.

As shown in FIG. 19 and FIG. 20 , an inside/outside air switching device136 is provided on the right side of the air conditioning device 37. Theinside/outside air switching device 136 is provided in the seat supportframe 138 and is located rightward between the seat attachment portion140 a and the bottom plate 141. On the right side of the seat base 31,an outside air introduction device 137 is provided. The outside airintroduction device 137 and the inside/outside air switching device 136are connected by a connection duct 152.

As shown in FIG. 20 , a fan accommodating portion 153 accommodating ablower fan is provided at the rear portion of the air conditioningdevice 37. A device main body portion 154 in which a heat exchanger isaccommodated is provided in the front portion of the air conditioningdevice 37. Air is sucked from the right side portion by the blower fanin the fan accommodating portion 153, and the sucked air is sent to thedevice main body portion 154 and warmed by the heat exchanger.

As shown in FIG. 20 , a first blowing part 155 for blowing conditionedair is provided in the front part of the device main body part 154. Thefirst blowing part 155 corresponds to the first opening groove 150 in astate in which the opening and closing cover 139 is closed (see FIG. 18). Thus, the conditioned air blown out from the first blowing part 155is blown into the room of the cabin 5 through the first opening groove150. In addition, a second blowing part 156 is provided on the upperpart of the right side surface of the device main body part 154. An airsupply duct 145 shown in FIG. 18 is connected to the second blowing part156.

As shown in FIGS. 21 to 24 , the inside/outside air switching device 136has a switching box 157, an operating shaft 158, a switching member 159,an operating member 160, and a switching spring 161. The switching box157 has a box body 162 and a cover plate 163.

As shown in FIG. 23 , the box body 162 has a bottom portion 162 a. Inthe present embodiment, the bottom portion 162 a is constituted of apart of the lower plate 141. Further, the box body 162 has a firstvertical plate (first plate) 164 and a second vertical plate (secondplate) 165 opposed to the first vertical plate 164. The first verticalplate 164 and the second vertical plate 165 are erected on the lowerplate 141. The box main body 162 has an upper end opening (one endopening) 166 (one end opening) in which a space (one end portion)between the upper end portion (one end portion) 164 a of the firstvertical plate 164 and the upper end portion (one end portion) 165 a ofthe second vertical plate 165. The first vertical plate 164 and thesecond vertical plate 165 (box main body 162) are formed such that thefront region is formed along the front-rear direction K1 and the rearregion is formed inside the airframe (on the air conditioning device 37side) as going backward as shown in the drawings. In addition, the firstvertical plate 164 and the second vertical plate 165 are opposed to eachother with a front region thereof spaced apart from the body widthdirection K2 by a substantially constant distance, and the rear regionthereof is wider toward the air conditioning device 37 side as shown inthe drawings.

As shown in FIG. 21 and FIG. 23 , a first spring hook portion 167 isprovided on the upper portion (the upper end portion 164 a side) of thefirst vertical plate 164. The first spring hooking portion 167 isprovided on the rear region side of the front region of the firstvertical plate 164. One end (rear end) of the switching spring 161 ishooked on the first spring hooking portion 167. The switching spring 161is constituted of a coil spring. The first spring hooking portion 167has an upper wall 167 a extending from the upper end of the firstvertical plate 164 toward the inside of the airframe and a rear wall 167b extending downward from the rear end of the upper wall 167 a. On theleft side of the front portion of the upper wall 167 a, a spring hookinghole 167 c through which one end of the switching spring 161 is insertedis formed. The spring hooking hole 167 c is constituted of an annularedge portion formed through the upper wall 167 a. The other end (frontend) of the switching spring 161 is hooked on the second spring hookingportion 185 formed on the operating member 160.

As shown in FIG. 23 and FIG. 25 , a support groove 168 is formed on theupper portion (one end portion side) of the first vertical plate 164.The upper end (one end) side of the first vertical plate 164 is open inthe support groove 168, and is formed from the upper end (one end) ofthe first vertical plate 164 toward the lower side. Further, the supportgroove 168 is provided in front of the first spring hooking portion 167.One end side (left end side) of the operating shaft 158 is inserted intothe supporting groove 168 from above (opening at the upper end side ofthe first vertical plate 164). The groove bottom 168 a of the supportgroove 168 is formed in a circular arc shape, and one end side of theoperation shaft 158 is supported (pivoted) to the groove bottom 168 a.Thus, the groove bottom 168 a of the support groove 168 is a pivotallysupporting portion pivotally supporting one end side of the operationshaft 158. The support groove 168 is an oblong long groove that moves ina direction away from the first spring hooking portion 167 as going fromthe groove bottom 168 a to the groove opening edge 168 b (toward theupper side). The groove edge portion 168 c on the upper side of thesupport groove 168 is a receiving surface that is a portion thatreceives an urging force acting on the operation shaft 158. The grooveedge portion 168 c is formed in an inclined shape to shift from thegroove bottom 168 a to the groove opening edge 168 b (toward the upperside) in a direction away from the first spring hooking portion 167.

As shown in FIG. 23 and FIG. 24 , an outside air intake port 169 forintroducing outside air into the switching box 157 is provided in thefront portion of the second vertical plate 165. The outside air intake169 is formed by a cylindrical body, and one end side thereof isinserted into the box main body 162 through the second vertical plate165. The inside airframe side (one end side) of the connection duct 152shown in FIG. 20 is connected to the outside air intake 169. The frontportion of the second vertical plate 165 has a shaft support portion 170that passes through and supports the other end side (right end side) ofthe operation shaft 158. The pivot support portion 170 is constituted ofan annular edge portion formed through the second vertical plate 165.The pivot support portion 170 is formed corresponding to the groovebottom 168 a (pivot support portion) of the support groove 168 in themachine width direction K2. In other words, the pivot support portion170 and the groove bottom 168 a of the support groove 168 are coaxialcentered. By pivotally supporting one end side of the operation shaft158 in the support groove 168 and pivotally supporting the other endside to the pivot support part 170, the operation shaft 158 is disposedbetween the upper portions of the first vertical plate 164 and thesecond vertical plate 165.

At the upper end of the front region of the second vertical plate 165,an engaging piece 171 extending upward is provided. A locking groove 172is formed in the locking piece 171. The locking piece 171 is providedbehind the pivot support portion 170.

As shown in FIG. 21 and FIG. 23 , the box main body 162 has a frontvertical plate 173 that closes between the front end portions of thefirst vertical plate 164 and the second vertical plate 165. On the upperend of the front vertical plate 173, a first fixing piece 174 extendingrearward is provided. As shown in FIG. 21 and FIG. 23 , the box mainbody 162 has a rear vertical plate 175 which closes between the rear endportions of the first vertical plate 164 and the second vertical plate165. In the rear longitudinal plate 175, the plate surface faces themachine inward direction (the side of the fan accommodating portion 153shown in FIG. 20 ). The rear vertical plate 175 is formed with acommunication port 177 (an annular edge portion penetrating the rearvertical plate 175) communicating with the fan accommodating portion153. The box body 162 communicates with the air conditioning device 37via the communication port 177. A second fixing piece 176 extendingoutward of the machine body is provided at the upper end of the rearvertical plate 175.

As shown in FIG. 23 and FIG. 24 , the box main body 162 has a partitionplate 178 in the front region. The partition plate 178 is disposedbetween the first vertical plate 164 and the second vertical plate 165and divides the interior of the box body 162 into a room on the side ofthe outside air intake port 169 and a room on the side of thecommunication port 177. The partition plate 178 has an inclined wall 178a and a lower wall 178 b. The inclined wall 178 a extends in an inclineddirection that moves downward as it goes backward from between the upperends of the first vertical plate 164 and the second vertical plate 165.The lower wall 178 b extends downward from the lower end of the inclinedwall 178 a and is connected to the lower plate 141 (the bottom portion162 a of the box body 162). An outside air intake port 179 is formed onthe lower side of the inclined wall 178 a. The outside air intake port179 is constituted of an annular opening edge portion formed through theinclined wall 178 a. The outside air introduced into the box body 162passes through the outside air intake 179 and flows to the communicationport 177 and is taken into the air conditioning device 37. That is, theoutside air intake port 179 is an opening for introducing the outsideair introduced into the box body 162 into the air conditioning device37.

As shown in FIG. 23 , the upper end portion 164 a of the first verticalplate 164, the upper end portion 165 a of the second vertical plate 165,the upper end portion 173 a of the front vertical plate 173, and theupper end portion 175 a of the rear vertical plate 175 form the upperend opening 166 of the box body 162.

As shown in FIG. 21 and FIG. 22 , the cover plate 163 is a lid memberthat closes the upper end opening 166 of the box main body 162. Thecover plate 163 is bolted to the first fixing piece 174 and the secondfixing piece 176 in a state of closing the upper end opening 166 of thebox main body 162. An engaging portion 180 inserted from the left sideinto the engaging groove 172 and engaged with the engaging piece 171 isprovided in the middle portion of the cover plate 163.

An inside air inlet 181 for taking inside air through the box main body162 and into the air conditioning device 37 is formed in the cover plate163. The inside air inlet 181 is constituted of a plurality of longgrooves (opening edge portions) 181 a. The elongated groove 181 a isconstituted of an elongated hole-shaped edge formed through the coverplate 163, and is formed in a rectangular shape elongated in the machinewidth direction K2. In the present embodiment, the inside air inlet 181is formed by arranging six long grooves 181 a in parallel in thefront-rear direction. The inside air inlet 181 is not limited to beingconstituted of a plurality of long grooves 181 a. That is, it may beconstituted of a single opening edge portion.

Further, the inside air intake 181 is located in the middle part (therear side of the front region) of the cover plate 163. Further, theinside air intake 181 is located behind the partition plate 178 in astate where the cover plate 163 is closed. Thus, the inside air intake181 introduces the inside air to the rear side of the partition plate178 in the box main body 162. The inside air taken into the box body 162is taken into the air conditioning device 37 via the communication port177.

As shown in FIG. 22 , the cover plate 163 has a retaining portion 182 onthe inner side (left side) of the body. The retaining portion 182prevents the member for preventing the operation shaft 158 from fallingoff, that is, the movement of the operating shaft 158 in the axialdirection to prevent the operating shaft 158 from falling off from thepivot portion 170 of the second vertical plate 165. The retainingportion 182 is formed by bending a part of the plate materialconstituting the cover plate 163 downward. That is, the retainingportion 182 extends downward from the left side edge portion of thecover plate 163. Further, the retaining portion 182 is positioned on thefront side of the inside air inlet 181. Further, the retaining portion182 is positioned in front of the first spring hooking portion 167 in astate where the cover plate 163 is closed. An escape hole 183 forallowing one end side of the operation shaft 158 to escape is formed inthe retaining portion 182. The relief hole 183 is constituted of anannular edge portion formed through the retaining portion 182.

In the present embodiment, the box main body 162 has the upper endopening 166, and the cover plate 163 is a member for closing the upperend opening 166, but this is not a limitation. For example, the opening(one end opening) of the box main body 162 closed by the cover plate 163may open forward, backward, or downward, and even if it is open to theleft or right.

As shown in FIG. 23 , the operation member 160 is constituted of a levermember, and one end side of the operation shaft 158 is fixed to one endportion (the base portion 160 a) of the operation member 160. Thus, theoperation member 160 can rotate the operation shaft 158 around its axis.One end side of the operating shaft 158 passes through the operatingmember 160 and protrudes to the left. A grip 184 is provided at theother end portion (distal end portion) of the operation member 160. Asecond spring hooking portion 185 to which the other end (front end) ofthe switching spring 161 is hooked is integrally formed at anintermediate portion of the upper portion of the operating member 160. AU-shaped groove 185 a for hooking the other end of the switching spring161 is formed in the second spring hooking portion 185 (see FIG. 22 ).

As shown in FIG. 23 , the switching member 159 is fixed to the operatingshaft 158. The switching member 159 selectively closes the inside airintake 181 and the outside air intake 179. The switching member 159 hasa plate member 159 a, a first abutting member 159 b, and a secondabutting member 159 c. The plate member 159 a constitutes the core bodyof the switching member 159, and is made of a rectangular platematerial. One end of the plate member 159 a in the plate surfacedirection is fixed to the operation shaft 158 along the axial centerdirection. The first abutting member 159 b and the second abuttingmember 159 c are formed of an elastic plate material such as a rubberplate. The first abutting member 159 b is superimposed and fixed to aplate surface on one side (upper side) of the plate member 159 a. Thesecond abutting member 159 c is superimposed and fixed to the platesurface of the other side (lower side) of the plate member 159 a.

The operating shaft 158 is pivotally supported on the box body 162 in astate where the operating member 160 and the switching member 159 arefixed. To attach the operating shaft 158, the operating member 160 andthe switching member 159 to the box main body 162, the switching member159 is disposed at the rear side of the partition plate 178 in the boxmain body 162. Next, the other end side of the operation shaft 158 isinserted into the pivot support portion 170 from the inside of the boxmain body 162. Thereafter, one end side of the operation shaft 158 isinserted into the support groove 168 from above. At this time, theoperation member 160 is positioned on the outer surface side of the boxbody 162 (the outer surface side of the first vertical plate 164). Thus,the operating shaft 158, the operating member 160, and the switchingmember 159 are easily attached to the box main body 162. The switchingmember 159 is positioned between the inside air intake 181 and theoutside air intake 179 in a state in which the operation shaft 158, theoperation member 160, and the switching member 159 are attached to thebox main body 162.

The cover plate 163 is assembled to the box body 162 in a state in whichthe operation shaft 158, the operation member 160, and the switchingmember 159 are attached to the box main body 162. When assembling thecover plate 163, the retaining portion 182 is positioned laterally (leftside) on the side opposite to the first vertical plate 164 with respectto the base portion 160 a of the operating member 160 (see FIG. 22 ).That is, the retaining portion 182 is arranged to face the firstvertical plate 164 via the base portion 160 a of the operating member160. As a result, the movement of the operating member 160 and theoperating shaft 158 in the axial direction is restricted by theretaining portion 182, and the operating shaft 158 is prevented fromcoming off. Thereafter, the switching spring 161 is hooked on the firstspring hooking portion 167 and the second spring hooking portion 185.

As shown in FIG. 24 , the switching member 159 is switched between thefirst switching position 186 indicated by an imaginary line and thesecond switching position 187 indicated by a solid line by rotating theoperating shaft 158 about its axis. The first switching position 186 isa position for closing the inside air intake 181. That is, at the firstswitching position 186, the switching member 159 (first abutting member159 b) abuts against the lower surface of the cover plate 163 so as toclose the inside air intake 181. As a result, outside air introducedinto the box body 162 from the outside air intake 169 passes through theoutside air intake 179 and is taken into the air conditioning device 37.That is, the first switching position 186 is a position where outsideair is taken into the air conditioning device 37.

The second switching position is a position for closing the outside airintake port 179. That is, at the second switching position 187, theswitching member 159 (the second abutting member 159 c) abuts againstthe upper surface of the partition plate 178 so as to close the outsideair intake port 179. As a result, the inside air passes through theinside air intake 181 and is taken into the air conditioning device 37.That is, the second switching position 187 is a position where theinside air is taken into the air conditioning device 37.

As shown in FIG. 24 , when the switching member 159 is positioned at thefirst switching position 186, the operating member 160 is depressed asindicated by an imaginary line. In this state, the axis of the switchingspring 161 is positioned below the axis of the operating shaft 158.Thus, the urging force of the switching spring 161 acts in the directionof pulling down the operating member 160 (the direction of holding theswitching member 159 at the first switching position 186). Due to thisurging force, the switching member 159 is held at the first switchingposition 186.

In a state where the switching member 159 is located at the secondswitching position 187, the operating member 160 is pulled up asindicated by the solid line. In this state, the axis of the switchingspring 161 is located above the axis of the operating shaft 158. Thus,the urging force of the switching spring 161 acts in a direction inwhich the operating member 160 is pulled up (a direction in which theswitching member 159 is held at the second switching position 187). Dueto this urging force, the switching member 159 is held at the secondswitching position 187.

As described above, by operating the operation shaft 158, the switchingspring 161 urges the switching member 159 toward the first switchingposition 186 and biases the switching member 159 toward the secondswitching position 187, and the urging force are switched. That is, byoperating the operation member 160, when the axis line of the switchingspring 161 reaches a position lower than the axis center of theoperation shaft 158, the urging force of the switching spring 161 movesin the direction of pulling down the operation member 160 (a directionof biasing the switching member 159 to the first switching position 186side). Also, by operating the operating member 160, when the axis lineof the switching spring 161 reaches a position higher than the axiscenter of the operating shaft 158, the urging force of the switchingspring 161 moves in the direction of pulling up the operating member 160(a direction of biasing the switching member 159 to the second switchingposition 186 side).

Next, the outside air introduction device 137 will be described.

As shown in FIG. 19 , FIG. 20 , and FIG. 26 , the outside airintroduction device 137 has a filter 188, a filter insertion portion 189into which the filter 188 is detachably inserted, and an outside airintroduction duct 190 into which outside air is introduced.

The filter 188 is a filter 188 for removing dust from outside air. Theoutside air from which the dust is removed by the filter 188 is sent tothe inside/outside air switching device 136. Thus, the filter 188 is afilter 188 that removes dust of the outside air before being taken intothe box main body 162. The filter 188 is formed in a rectangularparallelepiped and is elastically deformable.

As shown in FIG. 19 and FIG. 20 , the filter inserting portion 189 isdisposed on the right end side in the seat supporting frame 138. Asshown in FIG. 26 , the filter inserting portion 189 includes a side wall189 a, an upper wall 189 b extending outward from the upper end of theside wall 189 a, a lower wall 189 c extending downward from the lowerend of the side wall 189 a, and a rear wall 189 d extending downwardfrom the rear end of the side wall 189 a. The space between the frontend portions of the upper wall 189 b and the lower wall 189 c is opentoward the front. An opening portion between the front end portions ofthe upper wall 189 b and the lower wall 189 c is covered with theopening/closing cover 139 from the front. From this opening portion, thefilter 188 can be inserted into the filter insertion portion 189. Thus,the filter 188 is attached to the sheet insertion portion 189 providedin the seat supporting frame 138 so as to be removable from the frontside (one side) of the seat supporting frame 138.

As shown in FIG. 27B, in a state of being inserted into the filterinsertion portion 189 of the filter 188 to the back, the front end sideof the filter 188 is protruded toward the filter insertion portion 189to cover 139 side (forward). Then, in a closed state, the opening andclosing cover 139 presses the filter 188 in a direction to insert itinto the filter insertion portion 189.

As shown in FIG. 26 , the upper wall 189 b forms an arcuate cutout 189 ewhich is recessed from the front toward the rear. With this cutout 189e, it is easy to apply a finger or the like to the filter 188 whentaking out the filter 188 from the filter insertion portion 189. Acylindrical connecting portion 191 communicating with the inside of thefilter inserting portion 189 is provided under the side wall 189 a. Asshown in FIG. 27A and FIG. 27B, the connecting portion 191 is connectedto the outside of the body of the connecting duct 152 (the other endside).

As shown in FIG. 18 , the outside air introduction duct 190 is disposedbetween the filter 188 (filter insertion portion 189) and the secondside face portion 39 of the cabin 5.

As shown in FIG. 26 , the outside air introduction duct 190 includes aduct body 192 and a duct cover 193. The duct main body 192 includes afirst side wall 192 a, a front wall 192 b extending outward from thefront end of the first side wall 192 a, a front wall 192 b extendingforward from an end portion (right end) of the front wall 192 b on theouter side of the body and a rear wall 192 d extending outward from therear end of the first side wall 192 a. The right end of the upper wall189 b of the filter insertion portion 189 and the right end of the lowerwall 189 c are joined to the first side wall 192 a. A communicatingportion 194 for communicating the inside of the outside air introductionduct 190 and the inside of the filter inserting portion 189 is formedunder the first side wall 192 a. The communicating portion 194 is formedby an annular edge penetrating the first side wall 192 a. The attachingwall 192 c is attached to the lower portion of the second side surfaceportion 39 by bolts 192 e and 192 f (see FIG. 27B).

As shown in FIG. 26 , FIG. 27A and FIG. 27B, the duct lid 193 has asecond side wall 193 a opposed to the first side wall 192 a in themachine width direction K2, and a second side wall 193 b extendinginward from the upper end of the second side wall 193 a, an upper wall193 b, and a lower wall 193 c extending inward from the lower end of thesecond side wall 193 a. The upper wall 193 b covers between the upperend portions of the front wall 192 b and the rear wall 192 d. The lowerwall 193 c covers between the upper end portions of the front wall 192 band the rear wall 192 d. A communication port 195 communicating with theoutside air introduction port 46 formed in the second side face portion39 is provided on the upper portion of the second side wall 193 a. Thecommunication port 195 is formed by a plurality of elongated grooves 195a formed to extend through the second side wall 193 a and elongated inthe front-to-rear direction. The second side wall 193 a is provided witha plurality of eaves 196 extending in an inclined direction that movesdownward from the upper edge of each long groove 195 a toward theoutside of the airframe.

In the outside air introduction device 137, the outside air flows intothe outside air introduction duct 190 through the outside airintroduction port 46 and the communication port 195. The outside airflowing into the outside air introduction duct 190 flows into the filterinsertion portion 189 via the communication portion 194. The outside airflowing into the filter insertion portion 189 passes through the filter188 and is introduced into the switching box 157 through the connectionportion 191 and the connection duct 152.

In this embodiment, the working machine 1 includes a cabin 5, an airconditioning device 37 for air conditioning inside the cabin 5, a boxbody 162 communicating with the air conditioning device 37, having afirst board (first vertical board) 164, a second board (second verticalboard) 165 facing the first board 164, and having one end opening (upperend opening 166) opened between one end portion (upper end portion 164a) of the first plate 164 and one end portion (upper end portion 165 a)of the second plate 165, a cover plate 163 for closing one end opening(upper end opening 166) of the box main body 162, an operating shaft 158rotatably supported by the first plate 164 and the second plate 165, aswitching member 159 arranged in the box main body 162 and fixed to theoperating shaft 158, which rotates the operating shaft 158 to beswitched between a first switching position 186 to introduce the outsideair of the cabin 5 to the air conditioning device 37 and a secondswitching position 187 to introduce the inside air of the cabin 5 to theair conditioning device 37, and an operating member 160 fixed to one endside of the operating shaft 158 for rotating operation of the operatingshaft 158; the cover plate 163 has a retaining portion 182 which opposesvia at least a part of the operation member 160 and regulates themovement of the operation member 160 and the operation shaft 158 in theaxial direction so as to prevent the operation shaft 158 from comingoff.

According to the above configuration, since the cover plate 163 has theretaining portion 182 for preventing the operation shaft 158 from comingoff, it is not necessary to separately provide the bracket for pivotallysupporting the operating shaft and a retaining member for retaining theoperation shaft as in the above-described prior art, thus the number ofparts can be reduced. Further, by attaching the cover plate 163 to thebox main body 162, it is possible to prevent the operation shaft 158from being withdrawn, it is not necessary to perform an operation toattach the bracket for pivotally supporting the operating shaft and aretaining member for retaining the operation shaft as in theabove-described prior art, thus the manufacturing process can besimplified. This makes it possible to reduce the manufacturing cost ofthe working machine provided with the inside/outside air switchingmechanism.

Further, the retaining portion 182 is formed by bending a part of aplate material forming the cover plate 163. Thus, the retaining portion182 can be easily formed.

The first plate (first vertical plate) 164 has a support groove 168 thatopens to one end (upper end portion 164 a) side of the first plate 164and pivotally supports one end side of the operation shaft 158, thesecond plate (second vertical plate) 165 has a pivot support portion 170that penetrates the second plate 165 and pivotally supports the otherend side of the operation shaft 158.

According to the above configuration, with the switching member 159fixed to the operation shaft 158, the other end side of the operationshaft 158 is inserted into the pivot support portion 170 and one endside of the operation shaft 158 is inserted into the support groove 168,the operating shaft 158 and the switching member 159 can be mounted.This makes it easy to mount the operation shaft 158 and the switchingmember 159.

In addition, a first spring hooking portion 167 provided at one endportion (upper end portion 164 a) of the first plate (first verticalplate) 164, a second spring hooking portion 185 provided on theoperating member 160, a first spring and a switching spring 161 hookedon the hooking portion 167 and the second spring hooking portion 185.The supporting groove 168 is located between the first spring hookingportion 167 and the second spring hooking portion 185 and the groovebottom 168 a (groove edge portion 168 c) formed to be inclined so as tomove in a direction away from the first spring hooking portion 167toward the groove opening edge 168 b and the operating shaft 158 abutsagainst the operating member 160. When the operating member 160 isoperated, the supporting groove 168 is switched between the state inwhich the switching member 159 is biased toward the first switchingposition 186 by the switching spring 161 and the state in which theswitching member 159 is biased toward the second switching position 187by the switching spring 161. In this manner, the biasing force F1 of theswitching spring 161 (see FIG. 25 ) can be applied in a direction (rightangle or close to right angle) intersecting the receiving surface (thegroove edge portion 168 c) regardless of the operating angle of theoperating member 160, thus it is possible to prevent the operating shaft158 from coming out of the supporting groove 168.

When the switching member 159 is disposed at the first switchingposition 186, the urging force of the switching spring 161 acts in adirection to hold the switching member 159 at the first switchingposition 186, so that the switching member 159 moves to the secondswitching position 187 side, the urging force of the switching spring161 acts in a direction to hold the switching member 159 at the secondcutting position 187. Accordingly, it is possible to prevent theoperating shaft 158 from coming out of the support groove 168 againstthe intention by an external force such as vibration.

Further, the outdoor air of the cabin 5, which is disposed between thefirst plate (first vertical plate) 164 and the second plate (secondvertical plate) 165 and introduced into the box body 162, is supplied tothe air conditioning device 37A partition plate 178 formed with anoutside air intake 169 for taking in the inside of the cabin 5, thecover plate 163 has an inside air intake 181 for taking air inside thecabin 5 into the air conditioning device 37 through the interior of thebox main body 162, the member 159 opens the outside air intake port 169to close the inside air intake port 181 at the first switching position186 and opens the inside air intake port 181 at the second switchingposition 187 to close the outside air intake port 169. Thus, it ispossible to appropriately switch to the first switching position 186 andthe second switching position 187.

A cabin 5, the operator seat 6 disposed in the cabin 5, a seatsupporting frame 138 which is provided on the machine body 2 andsupports the operator seat 6 and accommodates the air conditioningdevice 37, an opening and closing cover 139 for covering one side of theseat supporting frame 138 in an openable and closable manner, a filter188 for removing dusts of the air outside the cabin 5 before being takeninto the box main body 162, provided in the seat supporting frame 138,and a filter insertion portion 189 to which the filter 188 is detachablyattached from one side of the seat supporting frame 138. When theopening and closing cover 139 is opened, a part of the filter 188 movesfrom the filter inserting portion 189 when the opening and closing cover139 is closed, the opening and closing cover 139 comes into contact withthe filter 188 and is pressed in the direction to insert the filter 188into the filter inserting portion 189. As a result, the cover forclosing the take-out port for taking out the filter 188 can be used alsoas the opening/closing cover 139, whereby it is possible to reduce thenumber of members and to reduce the number of assembling steps.

Further, since the filter 188 can function as a vibration isolatingmember for suppressing the vibration of the opening/closing cover 139due to vibrations of the machine body 2 or the like, the vibration proofmaterial for vibration proof at one end side of the open/close cover 139can be omitted. Thus, it is possible to reduce the number of parts andto reduce the manufacturing cost.

Next, the running frame 9 will be described.

As shown in FIG. 28 , the traveling frame 9 has a center frame 203, afirst side frame 204L provided on the left side of the center frame 203,and a second side frame 204R provided on the right side of the centerframe 203. And the machine body 2 is rotatably supported by the centerframe 203 via the orbiting bearing 8. The traveling mechanism 10 shownin FIG. 1 is mounted on the first side frame 204L and the second sideframe 204R.

The turn bearing 8 has an outer ring 205, an inner ring 206 provided onthe inner peripheral side of the outer ring 205 so as to be rotatablearound the turn axis, and an inner peripheral gear portion 207 formed onthe inner peripheral side of the inner ring 206. As shown in FIG. 31 ,the outer ring 205 is bolted to the turn base plate 56. That is, theouter ring 205 is attached to the machine body 2. The inner ring 206 isbolted to the center frame 203.

As shown in FIG. 28 , a pinion 208 is attached to the turning motor M2.The pinion 208 is driven by the turning motor M2 and rotates about itsaxis. The pinion 208 meshes with the inner peripheral gear portion 207.Thus, when the pinion 208 is driven by the turning motor M2, the pinion208 meshes with the inner peripheral gear portion 207 and moves in thecircumferential direction of the swing bearing 8. As a result, themachine body 2 rotates around the turn axis X1. A swivel joint 209 isdisposed at the center side of the swing bearing 8, that is, at theposition of the turn axis X1. The swivel joint 209 is a swivel jointthat enables operation fluid to be supplied and discharged between thehydraulic actuator on the traveling device 3 side and the control valveV1 on the machine body 2 side.

As shown in FIG. 31 , the swivel joint 209 has an outer sleeve 210 andan inner shaft 211. The inner shaft 211 is inserted into the outersleeve 210 so as to be rotatable around the longitudinal axis. The axisof rotation of the inner shaft 211 and the axis of rotation X1 coincidewith each other. The outer sleeve 210 has a first fixing portion 212 anda second fixing portion 213 in an upper portion thereof. The firstfixing portion 212 protrudes in one of the horizontal directions(frontward). The second fixing portion 213 protrudes to the other (rear)which is a horizontal direction opposite to the one direction. Anengagement plate 214 that engages with the turn base plate 56 androtates together with the turn base plate 56 is fixed to the inner shaft211.

As shown in FIG. 28 , FIG. 29 , and FIG. 31 , the center frame 203 has acentral frame portion 215 and four support legs 216A to 216D extendingfrom the central frame portion 215. The center frame portion 215 has atop plate 217, a bottom plate 218, a front plate 219, a rear plate 220,a left side plate 221L, and a right side plate 221R. The top plate 217is positioned above the bottom plate 218. In other words, the bottomplate 218 is provided below the top plate 217 with a space therebetween.The bottom plate 218 has an opening 222 formed by an edge penetratingthe bottom plate 218. The opening 222 is closed by the cover plate 223.The swivel joint 209 can be inserted into the center frame 203 (betweenthe top plate 217 and the bottom plate 218) through the opening 222. Thefront plate 219 is disposed between the top plate 217 and the front endportion of the bottom plate 218 and connects the top plate 217 and thebottom plate 218. The rear plate 220 is disposed between the top plate217 and the rear end portion of the bottom plate 218 and connects thetop plate 217 and the bottom plate 218. The left side plate 221 L isdisposed between the top plate 217 and the left end portion of thebottom plate 218 and connects the top plate 217 and the bottom plate218. The right side plate 221R is disposed between the top plate 217 andthe right end portion of the bottom plate 218 and connects the top plate217 and the bottom plate 218.

The support legs 216A and 216B connect the center frame portion 215 andthe first side frame 204L. The support legs 216C and 216D connect thecentral frame portion 215 and the second side frame 204R.

As shown in FIG. 28 , the inner race 206 of the swing bearing 8 isattached to the top surface of the top plate 217. Thus, the machine body2 is disposed above the top plate 217.

As shown in FIG. 29 and FIG. 30A, on the upper surface of the top plate217, an inner ring attachment portion 224 to which the inner ring 206 isattached is provided. A plurality of bolt insertion holes 225 forinserting bolts for fixing the inner race 206 are formed in the innerring attachment portion 224 so as to be spaced from each other in thecircumferential direction. The bolt insertion hole 225 is constituted ofan annular edge portion formed through the top plate 217.

The top plate 217 has a first joint support portion 226 for supportingthe first fixing portion 212 and a second joint support portion 227 forsupporting the second fixing portion 213. The first joint supportportion 226 protrudes from the inner ring attachment portion 224 towardthe swivel joint 209. In the present embodiment, the first joint supportportion 226 extends rearward from the front portion of the innercircumferential edge 228 of the inner ring attachment portion 224 towardthe swivel joint 209. The second joint support portion 227 is providedon the side opposite to the first joint support portion 226 andprotrudes from the inner ring attachment portion 224 toward the swiveljoint 209. In the present embodiment, the second joint support portion227 extends forward from the rear portion of the inner circumferentialedge 228 of the inner ring attachment portion 224 toward the swiveljoint 209. An interval is provided between the front end portion (rearend portion) 226 a which is the protruding side end portion of the firstjoint support portion 226 in the protruding direction and the front endportion (front end portion) 227 a which is the end portion of the secondjoint support portion 227 in the protruding direction. A swivel joint209 is disposed between the distal end portion 226 a and the distal endportion 227 a.

As shown in FIG. 30A and FIG. 30B, the first joint support portion 226includes a first base portion 229 and a first attachment portion 230.The first base portion 229 is a portion extending from the inner ringattachment portion 224 and reaching a midway portion in the projectingdirection of the first joint support portion 226. The first attachmentportion 230 is a portion extending from the first base portion 229 tothe distal end portion 226 a of the first joint support portion 226. Thefirst fixing portion 212 is mounted on the first attachment portion 230and is attached by a bolt 231 (see FIG. 31 ). The bolt 231 is screwedinto the first fixing portion 212 by passing through the firstattachment portion 230 from below the first attachment portion 230.

The first base portion 229 is gradually widened in a direction from thefirst attachment portion 230 to the inner ring attachment portion 224,and has a substantially fan shape in plan view. The first base portion229 has a first end edge 229 a which is an edge portion on one side inthe width direction (left side) and a second edge portion 229 b on theother side in the width direction (right side) which is the oppositeside edge portion of the first end edge 229 a.

The first edge 229 a is a concavely curved edge. The first end edge 229a is continuous with the first inner circumferential edge 228 a which isa part of the inner circumferential edge 228 of the inner ringattachment portion 224. The first inner circumferential edge 228 a isone (left side) portion of the inner circumferential edge 228 in themachine width direction K2. Further, the first end edge 229 a iscontinuous with the first side edge 230 a which is an edge portion onone side (left side) in the width direction of the first attachmentportion 230.

The second edge 229 b is a concavely curved edge. Further, the secondend edge 229 b is continuous with the second inner circumferential edge228 b which is a part of the inner circumferential edge 228 of the innerring attachment portion 224. The second inner circumferential edge 228 bis the other (right side) portion of the inner circumferential edge 228in the machine width direction K2. Further, the second end edge 229 b iscontiguous to the second side edge 230 b which is an edge portion on theother side (right side) in the width direction of the first attachmentportion 230.

As shown in FIG. 30A and FIG. 30B, the second joint support portion 227includes a second base portion 232 and a second attachment portion 233.The second base portion 232 is a portion extending from the inner ringattachment portion 224 and reaching a midway portion in the projectingdirection of the second joint support portion 227. The second attachmentportion 233 is a portion extending from the second base portion 232 tothe distal end portion 227 a of the second joint support portion 227.The second fixing portion 213 is placed on the second mounting portion233 and attached by a bolt 234 (see FIG. 31 ). The bolt 234 is screwedinto the second fixing portion 213 by inserting the second attachingportion 233 from below the second attaching portion 233.

The second base portion 232 is gradually widened in a direction from thesecond attachment portion 233 to the inner ring attachment portion 224,and has a substantially fan shape in plan view. The second base portion232 has a third edge 232 a which is an edge portion on one side (leftside) in the width direction and a third edge 232 a which is a fourthedge 232 b on the other side (right side) in the width direction whichis the opposite edge portion of the third edge 232 a.

The third edge 232 a is a concavely curved edge. Further, the third edge232 a is continuous with the first inner circumferential edge 228 a.Further, the third edge 232 a is contiguous to the third side edge 233 awhich is an edge portion on one side (left side) in the width directionof the second attachment portion 233.

The fourth edge 232 b is a concavely curved edge. Also, the fourth edge232 b is continuous with the second inner circumferential edge 228 b.Further, the fourth edge 232 b is contiguous to the fourth side edge 233b, which is an edge on the other side (right side) in the widthdirection of the second attachment portion 233.

As shown in FIG. 30A, the top plate 217 has a first edge portion 236constituting an opening, a second edge portion 237 constituting anopening, a third edge portion 238 constituting an opening, and a fourthedge portion 238 constituting an opening.

The first edge portion 236 constitutes an opening surrounded by thefirst inner circumferential edge 228 a, the first end edge 229 a, thefirst side edge 230 a, the third edge 232 a, and the third side edge 233a. The second edge portion 237 constitutes an opening surrounded by thesecond inner circumferential edge 228 b, the second edge 229 b, thesecond side edge 230 b, the fourth edge 232 b, and the fourth side edge233 b. The first edge portion 236 and the second edge portion 237communicate with each other between the front end portion 226 a of thefirst joint support portion 226 and the front end portion 227 a of thesecond joint support portion 227.

As described above, the top plate 217 has an opening composed of a firstedge portion 236, a second edge portion 237, and a communicating portionbetween the first edge portion 236 and the second edge portion 237. Aswivel joint 209 is arranged at the center of this opening. A firstjoint support portion 226 protrudes toward the center portion of theopening, and a second support portion 227 protrudes from a positionopposite to the first joint support portion 226 across the centerportion of the opening toward the center portion side.

To remove the swivel joint 209 from the traveling frame 9, the fixing ofthe swivel joint 209 to the first joint support portion 226 and thesecond joint support portion 227 is removed, and the swivel joint 209 ismoved to the lower side of the top plate 217. In order to move theswivel joint 209 downwardly of the top plate 217, the swivel joint 209can be moved to the lower side of the top plate 217 via the first edgeportion 236 by translating the swivel joint 209 to the left.Alternatively, by translating the swivel joint 209 to the right, it ispossible to move the swivel joint 209 downward of the top plate 217 viathe second edge portion 237.

Further, in order to move the swivel joint 209 downwardly of the topplate 217, the swivel joint 209 may be rotated about the turn axis X1.That is, by rotating the swivel joint 209 such that the first fixingportion 212 is disengaged from above the first attachment portion 230and the second fixing portion 213 is disengaged from above the secondmounting portion 233, the swivel joint 209 can be moved to the lowerside of the top plate 217 via the first edge portion 236 and the secondedge portion 237.

In the case of attaching the swivel joint 209 to the traveling frame 9,the procedure is performed in the reverse order of the removal.

As shown in FIG. 30B, the third edge portion 238 constitutes an opening(first opening portion) penetrating the first base portion 229 from theupper surface to the lower surface. The third edge portion 238 isgradually widened in a direction from the first attachment portion 230to the first base portion 229, and has a substantially fan shape in aplan view. The third edge portion 238 has a first side portion 238 a, asecond side portion 238 b, a third side portion 238 c, and a fourth sideportion 238 d.

The first side portion 238 a is an edge portion on one side (left side)of the machine width direction K2. The first side portion 238 a isformed as a convex curved edge curved in substantially the samedirection as the first end edge 229 a. The second side portion 238 b isa side portion facing the first side portion 238 a and an edge portionon the other side (the right side) of the machine width direction K2.The second side portion 238 b is formed as a convex curved edge curvedin substantially the same direction as the second end edge 229 b. Thethird side portion 238 c is a side portion located between the firstside portion 238 a and the second side portion 238 b and on the outerside in the radial direction of the swing bearing 8. The third sideportion 238 c is formed in a concave curved edge centered on the turnaxis X1. The fourth side portion 238 d is a side portion located betweenthe first side portion 238 a and the second side portion 238 b and onthe inner side in the radial direction of the swing bearing 8. Thefourth side portion 238 d is formed in a straight line extending in themachine width direction K2. The corner portion 238 e between the firstside portion 238 a and the third side portion 238 c is formed of aconcave curved edge. The corner portion 238 f between the second sideportion 238 b and the third side portion 238 c is formed of a concavecurved edge. The corner portion 238 g between the first side portion 238a and the fourth side portion 238 d is constituted of a concave curvededge. The corner portion 238 h between the second side portion 238 b andthe fourth side portion 238 d is constituted of a concave curved edge.

By forming the third edge portion 238 on the first base portion 229, acurved first arm portion 229 c and a curved second arm portion 229 d areformed. The first arm portion 229 c has a curved shape that moves to theleft (outside the body) as it goes forward. The second arm portion 229 dhas a curved shape that moves to the right (toward the outside of thebody) as it goes forward.

As shown in FIG. 30B, the fourth edge portion 239 constitutes an opening(second opening portion) penetrating the second base portion 232 fromthe upper face to the lower face. The third edge portion 238 isgradually widened in a direction from the second attachment portion 233to the second base portion 232, and has a substantially fan shape in aplan view. The third edge portion 238 has a fifth side portion 239 a, asixth side portion 239 b, a seventh side portion 239 c, and an eighthside portion 239 d.

The fifth side portion 239 a is an edge portion on one side (left side)of the machine width direction K2. The fifth side portion 239 a isformed by a convex curved edge curved in substantially the samedirection as the third edge 232 a. The sixth side portion 239 b is aside portion opposed to the fifth side portion 239 a and is an edgeportion on the other side (right side) of the machine width directionK2. The sixth side portion 239 b is formed by a convex curved edgecurved in substantially the same direction as the fourth edge 232 b. Theseventh side portion 239 c is a side portion located between the fifthside portion 239 a and the sixth side portion 239 b and on the outerside in the radial direction of the swing bearing 8. The seventh sideportion 239 c is formed by a concave curved edge centered on the turnaxis X1. The eighth side portion 239 d is a side portion located betweenthe fifth side portion 239 a and the sixth side portion 239 b and on theinner side in the radial direction of the swing bearing 8. The eighthside portion 239 d is formed in a linear shape extending in the machinewidth direction K2. The corner portion 239 e of the fifth side portion239 a and the seventh side portion 239 c is constituted of a concavecurved edge. The corner portion 239 f between the sixth side portion 239b and the seventh side portion 239 c is constituted of a concave curvededge. The corner portion 239 g between the fifth side portion 239 a andthe eighth side portion 239 d is constituted of a concave curved edge.The corner portion 239 h between the sixth side portion 239 b and theeighth side portion 239 d is constituted of a concave curved edge.

By forming the fourth edge portion 239 on the second base portion 232, acurved third arm portion 232 c and a curved fourth arm portion 232 d areformed. The third arm portion 232 c is curved so as to move leftward(outward of the body) as going backward. The fourth arm portion 232 d isin a curved shape that moves to the right (toward the outside of thebody) as going backward.

As shown in FIG. 30A, the third edge portion 238 and the fourth edgeportion 239 are provided below the movement trajectory 240 of the pinion208. In FIG. 30A, reference numeral 240 a indicates the outer peripheralside of the moving tracK240, and reference numeral 240 b indicates theinner peripheral side of the moving tracK240.

Next, the hose guide 202 that holds the hydraulic hose 201 disposedthrough the swing bracket 14 will be described.

FIG. 32 , FIG. 33 , and FIG. 34 , the swing bracket 14 includes a firstside wall portion 241, a second side wall portion 242, a rotationsupport portion 243, a boom connection portion 244, a first cylindercoupling portion 245, and a second cylinder connecting portion 246. Thefirst side wall portion 241 is provided on the left side of the secondside wall portion 242 with a certain distance. The rotation supportportion 243 is a portion which is supported by the support bracket 58 soas to be rotatable about the vertical axis. That is, the swing bracket14 has a rotation support portion 243 which is supported on the machinebody 2 so as to be rotatable around the vertical axis.

The rotation support portion 243 is positioned on the rear side of thefirst side wall portion 241 and the second side wall portion 242. Therotation support portion 243 has a first bracket coupling portion 247and a second bracket coupling portion 248 positioned below the firstbracket coupling portion 247. The first bracket coupling portion 247connects upper portions of rear portions of the first side wall portion241 and the second side wall portion 242. The second bracket couplingportion 248 connects the lower portion of the rear portion of the firstside wall portion 241 and the second side wall portion 242.

The first bracket coupling portion 247 has an upper side wall portion247 a and a lower side wall portion 247 b positioned below the upperside wall portion 247 a. A first connecting pin 249 is provided over theupper side wall portion 247 a and the lower side wall portion 247 b. Thefirst bracket coupling portion 247 is connected to the first supportingportion 61A via the first connecting pin 249 so as to be rotatablearound the longitudinal axis.

The second bracket coupling portion 248 has an upper side wall portion248 a and a lower side wall portion 248 b positioned below the upperside wall portion 248 a. A second connecting pin 250 is provided overthe upper side wall portion 248 a and the lower side wall portion 248 b.The second bracket coupling portion 248 is connected to the secondsupporting portion 61B via the second connecting pin 250 so as to berotatable around the longitudinal axis.

As shown in FIG. 35 , a first hose guide attachment portion 251 and asecond hose guide attachment portion 252 are provided at the frontportion (rotation support portion 243) of the upper side wall portion247 a of the first bracket coupling portion 247. The first hose guideattachment portion 251 is located at the left portion of the swingbracket 14 and the second hose guide attachment portion 252 is locatedat the right portion of the swing bracket 14. The upper surface of thefirst hose guide attachment portion 251 and the second hose guideattachment portion 252 are formed to be flat. A thread hole 251 a isformed in the first hose guide attachment portion 251. A thread hole 252a is formed in the second hose guide attachment portion 252.

As shown in FIG. 32 and FIG. 33 , the boom connecting portion 244 has afirst portion 244 a provided on the upper portion of the first side wallportion 241 and a second portion 244 b provided on the upper portion ofthe second side wall portion 242. A base portion of the boom 15 ispivotally supported by the boom connecting portion 244 via a thirdconnecting pin 253 provided between the first portion 244 a and thesecond portion 244 b (see FIG. 1 ). The first cylinder coupling portion245 has a first portion 245 a provided at the front portion of the firstside wall portion 241 and a second portion 245 b provided at the frontportion of the second side wall portion 242. One end side of the boomcylinder C3 is pivotally supported by the first cylinder connectingportion 245 via a fourth connecting pin 254 provided across the firstportion 245 a and the second portion 245 b (see FIG. 1 ). The secondcylinder coupling portion 246 has a first portion 246 a projectingrightward from the lower portion of the second side wall portion 242 anda second portion 246 b located below the first portion 246 a andprotruding rightward from the lower portion of the second side wallportion 242. A fifth connecting pin 255 is provided in the secondcylinder connecting portion 246 over the first portion 246 a and thesecond portion 246 b. One end side of the swing cylinder C2 is pivotallysupported by the second cylinder connecting portion 246 via a fifthconnecting pin 255.

As shown in FIG. 34 , the hydraulic hoses 200 and 201 are routed fromthe machine body 2 side (control valve V1) through the swing bracket 14to the working device 4 side. The hydraulic hoses 200 and 201 arearranged to pass between the first bracket coupling portion 247 and thesecond bracket coupling portion 248 and between the first side wallportion 241 and the second side wall portion 242. The hydraulic hose 200is a hose for sending and returning operation fluid to and from the boomcylinder C3. The hydraulic hose 201 is a hose for sending and returningoperation fluid to a hydraulic actuator (mounting actuator) that drivesthe arm cylinder C4, the bucket cylinder C5, and a work implementseparately mounted on the working device 4.

As shown in FIG. 32 and FIG. 34 , the swing bracket 14 is provided witha hose guide 202 for holding the hydraulic hose 201 arranged through theswing bracket 14.

As shown in FIG. 35 and FIG. 36 , the hose guide 202 includes a hoseretainer 256, a holder bracket 257, and a fastener 258. The hoseretainer 256 is a member that holds the hydraulic hose 201. That is, thehose guide 202 is a member for holding the hydraulic hose 201 for thearm cylinder C4, the bucket cylinder C5 and the attached actuator.

As shown in FIG. 34 , the hose retainer 256 is positioned in front ofthe first bracket coupling portion 247. As shown in FIG. 36 , the hoseretainer 256 has a first block member 259, a second block member 260, aholding member 261, a first sleeve 262, and a second sleeve 263. Thefirst block member 259 and the second block member 260 are formed of anelastic member such as rubber. In the first block member 259, four hosepassing holes 264A to 264D and two recessed portions 265A and 265B areformed.

The hose through-holes 264A to 264D are holes through which thehydraulic hose 201 is passed, and are formed by columnar edges formedthrough the first block member 259 in the longitudinal direction. In thefirst block member 259, slits 266 communicating with the respective hosepassing holes 264A to 264D are formed corresponding to the respectivehose passing holes 264A to 264D. By elastically deforming the firstblock member 259 to open the slit 266, it is possible to pass thehydraulic hose 201 through the hose through holes 264A to 264D.

The recesses 265A and 265B are portions for forming through holes forallowing passage of the hydraulic hose 201. The recesses 265A and 265Bare formed in a semicircular column shape having a longitudinal axis inthe rear part of the first block member 259. In addition, an insertionhole 267L is formed in the left portion of the first block member 259.An insertion hole 267R is also formed in the right portion of the firstblock member 259. Each of the insertion holes 267L and 267R is formed bya columnar edge portion formed to penetrate through the first blockmember 259 in the front-rear direction. A positioning member 268 isprovided at the center of the front portion of the first block member259.

The second block member 260 is positioned behind the first block member259. In the second block member 260, two recesses 269A and 269B areformed. The recesses 269A and 269B are portions for forming a throughhole for allowing the hydraulic hose 201 to pass through. The recesses269A and 269B are formed in a semicircular column shape having alongitudinal axis in the front portion of the second block member 260.When the front surface of the second block member 260 is superimposed onthe rear surface of the first block member 259, through holes are formedfor the passage of one hydraulic hose 201 by the recess 265A and therecess 269A, and the other recesses 265B and 269B, a through holethrough which one hydraulic hose 201 passes is formed. An insertion hole270L is formed in the left portion of the second block member 260. Aninsertion hole 270R is also formed in the right portion of the secondblock member 260. Each of the insertion holes 270L and 270R is formed bya columnar edge portion formed to pass through the second block member260 in the front-rear direction. When the front surface of the secondblock member 260 is overlapped with the rear surface of the first blockmember 259, the insertion hole 267L and the insertion hole 270Lcommunicate with each other, and the insertion hole 267R and theinsertion hole 270R communicate with each other. A positioning member271 is provided at the center of the rear surface of the second blockmember 260 (see FIG. 35 ).

The pressing member 261 is a member that is superimposed on the frontsurface of the first block member 259 and presses the first block member259 and the second block member 260 in cooperation with the holderbracket 257. The pressing member 261 is formed of a plate material. Apositioning hole 272 through which the positioning member 268 isinserted is formed in the central portion of the pressing member 261.The positioning hole 272 is constituted of an annular edge portionformed through the pressing member 261. At the lower end of the holdingmember 261, a bar 273 is provided. This rod member 273 is a member forprotecting the hydraulic hose 200 when the hydraulic hose 200 for theboom cylinder C3 arranged under the hose guide 202 hits the hoseretainer 256, and has a cylindrical shape as shown in the drawings.

The front end of the first sleeve 262 is fixed to the left part of thepressing member 261 and protrudes rearward from the pressing member 261.Female threads are cut in the inner peripheral surface of the firstsleeve 262. That is, the inner peripheral surface of the first sleeve262 is formed as a thread hole. The first sleeve 262 is inserted throughthe insertion hole 267L and the insertion hole 270L. The front end ofthe second sleeve 263 is fixed to the right part of the pressing member261 and protrudes rearward from the pressing member 261. Female threadsare cut in the inner peripheral surface of the second sleeve 263. Thatis, the inner peripheral surface of the second sleeve 263 is formed as athread hole. The second sleeve 263 is inserted through the insertionhole 267R and the insertion hole 270R.

The holder bracket 257 is formed of a plate material and includes aholding portion 276 a, a mounting stay portion 275, a connecting portion276 b, and a reinforcing plate 277. The holding portion 276 a holds thefirst block member 259 and the second block member 260 therebetween (incooperation with the holding member 261) with the holding member 261. Apositioning hole 278 through which the positioning member 271 isinserted is formed in the central portion of the holding portion 276 a.The positioning hole 278 is constituted of an annular edge portionformed through the pressing member 261. A first bolt insertion hole 279Lis formed in the left portion of the holding portion 276 a. A secondbolt insertion hole 279R is formed in the right portion of the holdingportion 276 a. The first bolt insertion hole 279L and the second boltinsertion hole 279R are formed by an annular edge part formed to passthrough the holding part 276 a.

The attachment stay portion 275 is a portion that is attached to therotation support portion 243 from above. That is, the holder bracket 257has an attachment stay portion 275 attached to the rotation supportportion 243 from above. The left portion of the attachment stay portion275 is superimposed on the first hose guide attachment portion 251, andthe right portion of the attachment stay portion 275 is superimposed onthe second hose guide attachment portion 252. The mounting stay portion275 is attached to the rotation support portion 243 (the upper side wallportion 247 a of the first bracket coupling portion 247) by the twobolts 280A and 280B. That is, the bolt 280A passes through the mountingstay portion 275 from above and is screwed into the thread hole 251 a.Further, the bolts 280A and 280B pass through the mounting stay portion275 from above and are screwed into the thread hole 252 a.

The connecting portion 276 b extends downward from the front portion ofthe mounting stay portion 275 and is connected to the upper portion ofthe holding portion 276 a. The reinforcing plate 277 is provided fromthe lower surface of the mounting stay portion 275 to the upper part ofthe rear surface of the holding portion 276 a.

The fastener 258 is a component for attaching the hose retainer 256 tothe holder bracket 257, and is constituted of bolts. The fastener 258includes a first mounting bolt 281 and a second mounting bolt 282. Thefirst mounting bolt 281 has a screw shaft portion 281 a and a headportion (tightening operation portion) 281 b. The second mounting bolt282 also has a screw shaft portion 282 a and a head portion (tighteningoperation portion) 282 b. The threaded shaft portions 281 a and 282 aare portions formed by cutting a male thread on the outer periphery ofthe columnar member. The head portions 281 b and 282 b are portionsengaging with tools for rotating the screw shaft portions 281 a and 282a, and are formed in a hexagonal prism shape. The screw shaft portion281 a of the first mounting bolt 281 is screwed into the first sleeve262 by inserting the first bolt insertion hole 279L from the rear. Thescrew shaft portion 282 a of the second mounting bolt 282 is screwedinto the second sleeve 263 by inserting the second bolt insertion hole279R from the rear.

As shown in FIG. 34 , in a state in which the holder bracket 257 isattached to the swing bracket 14 and the fastener 258 is attached to theholder bracket 257, the first attachment bolt 281 (fastener 258) and thesecond attachment bolt 282 (fastening The head portions 281 b and 282 bof the tool 258) face the rotation support portion 243 side. That is,the hose guide 202 is a fastener 258 for attaching the hose retainer 256to the holder bracket 257, and is fastened with the fastening operationportions 281 b and 282 b facing the rotation support portion 243 side ina state of being attached to the holder bracket 257 and a fastener 258.

The hydraulic hose 201 is attached to the hose guide 202 in a state inwhich the hose guide 202 is removed from the swing bracket 14 and thehydraulic hose 201 is not connected to the hydraulic actuator. Theprocedure for attaching the hydraulic hose 201 to the hose guide 202will be described below.

First, the hydraulic hose 201 arranged through the swing bracket 14 ispassed through the hose passing holes 264A to 264D of the first blockmember 259, and the recesses 265A and 265B of the first block member 259and the recess 265A of the second block member 260. Next, with thesecond block member 260 overlapped with the first block member 259, thefirst sleeve 262 is inserted through the insertion hole 267L and theinsertion hole 270L and the second sleeve 263 is inserted into theinsertion hole 267R and the insertion hole 270R and the pressing member261 is superimposed on the front surface of the first block member 259.In this state, the first mounting bolt 281 is screwed into the firstsleeve 262 through the first bolt insertion hole 279L from behind theholding portion 276 a, and the second mounting bolt 282 is screwed fromthe rear of the holding portion 276 a to the second bolt insertion hole279R into the second sleeve 263.

As described above, the hydraulic hose 201 is attached to the hose guide202.

After attaching the hydraulic hose 201 to the hose guide 202, the holderbracket 257 (hose guide 202) is attached to the swing bracket 14.

In the present embodiment, the working machine 1 includes a travelingframe 9 having a top plate 217 having an opening, a swivel base (machinebody 2) disposed on the traveling frame 9 so as to be able to turn aboutthe center of the opening as a turn axis, and a swivel joint 209arranged at the center of the opening. The top plate 217 has a firstjoint support portion 226 projecting toward the center portion side andsupporting the swivel joint 209, a first joint support portion 226 and asecond joint support portion 227 which protrudes toward the center fromthe position opposite to the support portion 226 and supports the swiveljoint 209. The first joint support portion 226 has a first openingpenetrating from the upper surface to the lower surface and a secondopening penetrating from the upper surface to the lower surface isformed in the second joint support portion 227.

As a result, it is possible to reduce the area on which the foreignmatter rides on the first joint support portion 226 and the second jointsupport portion 227. Further, foreign matter on the first joint supportportion 226 and the second joint support portion 227 can be droppeddownward from the first opening portion and the second opening portion.Thus, foreign matters can be prevented from accumulating on the firstjoint support portion 226 and the second joint support portion 227.

In addition, a turning motor M2 attached to the swivel base (machinebody 2), an outer ring 205 attached to the swivel base (machine body 2),and an outer ring 205 provided on the inner periphery side of the outerring 205 so as to be rotatable about the turn axis, and an inner ring206 having an inner peripheral gear portion 207 formed on the innerperipheral side thereof, a swing bearing 8 meshing with the innerperipheral gear portion 207 and driven to rotate by the turning motorM2, And a moving pinion 208. The running frame 9 has an inner ringattachment portion 224 shaped annularly to which the inner ring 206 isattached, and the first joint supporting portion 226 and the secondjoint supporting portion 227 extend from the inner ring attachmentportion 224 to the center portion and the first opening portion and thesecond opening portion are provided below the movement locus of thepinion 208.

Thereby, it is possible to suppress accumulation of foreign matter onthe movement trajectory 240 of the pinion 208, and to make it difficultfor the pinion 208 to be damaged due to contact with foreign matter.

In addition, the swivel joint 209 has a first fixing portion 212projecting in one direction in the horizontal direction and a secondfixing portion 213 projecting in the other horizontal direction oppositeto the one direction, and the first joint support portion 226 has afirst attachment portion 230 on which the first fixing portion 212 ismounted and a first base portion 229 which gradually widens in adirection away from the first attachment portion 230 and the secondjoint support portion 227 has a second mounting portion 233 on which thesecond fixing portion 213 is mounted and a second base portion 232 whichgradually widens in a direction away from the second mounting portion233, and the first opening portion (third edge portion 238) is providedon the first base portion 229 and gradually widened in a direction awayfrom the first attachment portion 230 and the second opening portion(fourth edge portion 239) is provided in the second base portion 232. Itis gradually widely formed in the direction away from the part 233.

Thereby, it is possible to suppress the accumulation of foreign matteron the first joint support portion 226 and the second joint supportportion 227 while ensuring the rigidity of the first joint supportportion 226 and the second joint support portion 227.

Further, a swing bracket 14 having a rotation support portion 243rotatably supported on a swivel base (machine body 2) about a verticalaxis, a hydraulic hose 201 disposed through the swing bracket 14, ahydraulic hose 201, a holder bracket 257 attached to the swing bracket14, and a fastener 258 for attaching the hose retainer 256 to the holderbracket 257. In a state where the fastener 258 is attached to the holderbracket 257, the rotation support portion And a fastener 258 havingfastening operation portions 281 b and 282 b facing the side 243.

In the above configuration, in a state of being attached to the holderbracket 257, the tightening operation portion of the fastener 258 facesthe rotation support portion 243 side. As a result, the operation offastening the fastener 258 and attaching the hose retainer 256 to theholder bracket 257 can be performed from above the hydraulic hose 201.That is, the tightening direction of the fastener 258 can be a directionfrom above to below the hydraulic hose 201. This makes it easy to mountthe hydraulic hose 201 (tightening operation of the fastener 258).

Further, the holder bracket 257 has an attachment stay portion 275attached to the rotation support portion 243 from above. Since there isno member or the like which is an obstacle to mounting above therotation support portion 243, attachment stay portion 275 can beattached easily. Further, since the attachment stay portion 275 can beattached to the rotation support portion 243 from above, the attachmentwork of the attachment stay portion 275 is a work from the top in astanding state, so that the attachment work can be carried out easily.

Next, the structure of the bonnet center 24 will be described.

First, the configuration of the rear lower part of the cabin 5 placed onthe bonnet center 24 will be described.

As shown in FIG. 37 , the rear lower frame 53 of the cabin 5 includes arear horizontal member (horizontal member) 286, a first rear assembledportion 287, a second rear assembled portion 288, a plurality of sealingmembers (a first seal 289, a second seal 290, a third seal 291). Therear cross member 286 is formed as a modified cylindrical body by theextruded steel (see FIG. 39A) and is provided between the lower endportions of the first rear pillar portion 79 and the second rear pillarportion 80. As shown in FIG. 40 , the rear cross member 286 has a frontlower wall 286 a forming the lower surface of the front portion and arear lower wall 286 b forming the lower surface of the rear portion. Thefront lower wall 286 a is formed to have a wider front-rear width thanthe rear lower wall 286 b. Further, the front lower wall 286 a is formedat a position higher than the rear lower wall 286 b.

As shown in FIG. 42 and FIG. 43 , the first rear assembling portion 287is formed of a plate material and is fixed to the lower surface on theleft side of the front lower wall 286 a. The first rear mount 50 isassembled to the first rear assembling portion 287. An opening 292through which the first rear mount 50 is inserted is formed in a portionof the front lower wall 286 a corresponding to the first rear mount 50.The opening 292 is constituted of an annular edge formed through thefront lower wall 286 a of the rear cross member 286. The second rearassembling portion 288 is formed of a plate material and is fixed to thelower surface on the right side of the front lower wall 286 a. Thesecond rear mount 51 is assembled to the second rear assembling portion288. An opening 293 through which the second rear mount 51 is insertedis formed in a portion of the front lower wall 286 a corresponding tothe second rear mount 51. The opening 293 is constituted of an annularedge portion formed through the front lower wall 286 a of the rear crossmember 286. In the present embodiment, the first rear mount 50 and thesecond rear mount 51 are assembled to the cabin 5. However, the presentinvention is not limited to this. For example, the first rear mount 50and the second rear mount 51 attached to a beam member 67 and the secondrear mount 51, as shown in the drawings.

The first seal 289 is provided over the lower surface side of the leftend portion of the rear horizontal member 286 and the lower end portionof the first rear pillar portion 79. The second seal 290 is providedover the lower surface side of the right end portion of the rearhorizontal member 286 and the lower end of the second rear columnportion 80. The third seal 291 is provided over the first seal 289 andthe second seal 290. The third seal 291 is provided on the rear side ofthe rear horizontal member 286 and on the rear side of the first rearmount 50 and the second rear mount 51. Further, in the presentembodiment, the third seal 291 is constituted of two members of a frontseal member 291A and a rear seal member 291B which is in contact withthe rear surface of the front seal member 291A, and is fixed to the rearlower wall 286 b (See FIG. 40 ).

As shown in FIG. 38 , the bonnet center 24 has a front center part 294,a left side part 295, a right side part 296, a placing part 297, and arear upper part 298. As shown in FIG. 39A, FIG. 39 B, and FIG. 42 , thebonnet center 24 has a first wall portion 299 on the interior 5A side ofthe cabin 5 and a second wall portion 300 on the engine room E2 side,and is formed in a hollow structure having an air layer between thefirst wall portion 299 and the second wall portion 300. For example, thebonnet center 24 is formed of a synthetic resin product having a hollowstructure formed by blow molding or rotational molding.

As shown in FIG. 4 , the front center portion 294 is located at aposition corresponding to the operator seat 6 (behind the operator seat6). The left side portion 295 is located on the left side of the frontcenter portion 294 and on the left side of the operator seat 6. Thelower surface (see FIG. 6 ) of the rear portion of the first sidesurface portion 38 of the cabin 5 comes into contact with the left sideportion 295 via the seal material 38 a. The right side portion 296 islocated on the right side of the front center portion 294 and on theright side of the operator seat 6. The lower surface (see FIG. 6 ) ofthe rear portion of the second side surface portion 39 is in contactwith the right side portion 296 via the sealing material 39 a. As shownin FIG. 38 and FIG. 39A, the front center portion 294 is immersed thanthe left side portion 295, the right side portion 296 and the placingportion 297. In the main body portion 294 a of the front center portion294, a check opening 301 is formed. The inspection opening 301 is closedby a lid member 294 b having a hollow structure from the front side, andthe lid member 294 b is pressed by a plurality of holding plates 303A,303B, and 303C bolted to the main body portion 294 a.

As shown in FIG. 38 and FIG. 39A, the mounting portion 297 extendsrearward from the upper portion of the front center portion 294.Further, the placing portion 297 is provided between the upper portionof the left side portion 295 and the upper portion of the right sideportion 296. The placing portion 297 is a portion constituting the uppersurface side of the engine room E2 (covering the upper part of theengine E1), and is placed and supported on the beam member 67(supporting portion). As shown in FIG. 1 , the rear portion of the cabin5 is placed on the placing portion 297. That is, the rear lower frame53, the first rear pillar portion 79, and the second rear pillar portion80 are placed via the first seal 289, the second seal 290 and the thirdseal 291.

As shown in FIG. 38 , the rear upper portion 298 is provided on theright side and the rear side of the placing portion 297. The rear upperportion 298 constitutes the upper surface side of the engine room E2together with the placement portion 297. The first wall portion 299 inthe rear upper portion 298 is formed higher than the placement portion297 (see FIG. 39B). Conversely, the first wall portion 299 of theplacement portion 297 is recessed downward from the rear upper portion298.

As shown in FIG. 38 , the placing portion 297 includes a plurality ofreinforcing portions (a first reinforcing portion 304, a secondreinforcing portion 305), a plurality of installing portions (a firstinstalling portion 306, a second installing portion 307), and aplurality of screw insertion portions (a first screw insertion portion308 and a second screw insertion portion 309).

The first reinforcing portion 304 and the second reinforcing portion 305are provided on the center side of the mounting portion 297 in themachine width direction K2. The first reinforcing portion 304 and thesecond reinforcing portion 305 are provided so as to be distributed tothe left and the right with the center of the placement portion 297 inthe body width direction K2 as a boundary. The first reinforcing portion304 is located on the left side of the second reinforcing portion 305.The first installing portion 306 is provided on the left side of theplacing portion 297. The second installation portion 307 is provided onthe right side of the placement portion 297. That is, the reinforcingportions (the first reinforcing portion 304 and the second reinforcingportion 305) are provided between the first installation portion 306 andthe second installation portion 307.

The first screw insertion portion 308 is provided between the firstreinforcing portion 304 and the first installation portion 306. Thesecond screw insertion portion 309 is provided between the secondreinforcing portion 305 and the second installation portion 307. Inother words, the reinforcing portions (the first reinforcing portion 304and the second reinforcing portion 305) are provided between the firstscrew insertion portion 308 and the second screw insertion portion 309.Further, the first screw insertion portion 308 and the second screwinsertion portion 309 are provided between the first installationportion 306 and the second installation portion 307. A plurality ofreinforcing portions (a first reinforcing portion 304, a secondreinforcing portion 305), a plurality of installation portions (a firstinstallation portion 306, a second installation portion 307) and aplurality of screw insertion portions (a first screw insertion portion308, a screw insertion portion 309) are formed side by side in themachine width direction K2.

As shown in FIG. 40 and FIG. 41A, a third seal 291 is positioned behindthe first reinforcing portion 304 and the second reinforcing portion305. The third seal 291 abuts on the first wall portion 299 of theplacing portion 297. That is, the rear portion of the cabin 5 has asealing material that abuts against the first wall portion 299 of theplacing portion 297. The second wall portion 300 of the placing portion297 is in contact with the beam member 67 (supporting portion).

As shown in FIG. 40 and FIG. 41A, the first reinforcing portion 304 hasa first hole edge portion 304 a, a second hole edge portion 304 b, and arib wall 304 c.

The first hole edge portion 304 a is an annular edge portion formedthrough the first wall portion 299 of the placement portion 297. Thefirst hole edge portion 304 a is formed in a horizontally elongated ovalshape (oblong shape) long in the machine width direction K2 in a planview. The first hole edge portion 304 a is located in the interior 5A ofthe cabin 5 in front of the third seal 291 (sealing material). A frontlower wall 286 a of the rear horizontal member 286 is positioned abovethe first hole edge 304 a.

The second hole edge portion 304 b is an annular edge portion formedthrough the second wall portion 300 of the placement portion 297. Thesecond hole edge portion 304 b is formed below (substantially directlybelow) the first hole edge portion 304 a. The second hole edge portion304 b is formed in an oblong elliptical shape (elliptical shape) long inthe machine width direction K2 in a plan view. The second hole edgeportion 304 b is formed substantially in the same shape as the firsthole edge portion 304 a. The second hole edge portion 304 b is closed bythe beam member 67 (support portion).

The rib wall 304 c is formed in a horizontally elongated ellipticalcylindrical shape (long cylindrical shape) long in the machine widthdirection K2. The upper end of the rib wall 304 c is connected to thecircumferential edge of the first hole edge portion 304 a. The lower endof the rib wall 304 c is connected to the circumferential edge of thesecond hole edge 304 b. Thus, the rib wall 304 c connects the entireperiphery of the circumferential edge of the first hole edge portion 304a and the entire circumferential edge of the circumferential edge of thesecond hole edge portion 304 b. That is, the reinforcing portionreinforces the hollow structure by connecting the first wall portion 299and the second wall portion 300.

As shown in FIG. 40 and FIG. 41 A, the second reinforcing portion 305also has a first hole edge portion 305 a, a second hole edge portion 305b, and a rib wall 305 c. The first hole edge portion 305 a is an annularedge portion formed through the first wall portion 299 of the placementportion 297. The first hole edge portion 305 a is formed in ahorizontally elongated oval shape (elliptical shape) long in the machinewidth direction K2 in a plan view. The first hole edge portion 305 a islocated in the interior 5A of the cabin 5 in front of the third seal 291(sealing material). A front lower wall 286 a of the rear horizontalmember 286 is positioned above the first hole edge portion 305 a.

The second hole edge portion 305 b is an annular edge portion formedthrough the second wall portion 300 of the placement portion 297. Thesecond hole edge portion 305 b is formed below (substantially directlybelow) the first hole edge portion 305 a. The second hole edge portion305 b is formed in an oblong elliptical shape (elliptical shape)elongated in the machine width direction K2 in a plan view. The secondhole edge portion 305 b is formed to have substantially the same shapeas the first hole edge portion 305 a. The second hole edge portion 305 bis closed by the beam member 67 (support portion).

The rib wall 305 c is formed in a horizontally elongated ellipticalcylindrical shape (long cylindrical shape) elongated in the machinewidth direction K2. The upper end of the rib wall 305 c is connected tothe circumferential edge of the first hole edge portion 305 a. The lowerend of the rib wall 305 c is connected to the circumferential edge ofthe second hole edge portion 305 b. Thus, the rib wall 305 c connects(connects) the entire periphery of the circumferential edge of the firsthole edge portion 305 a and the entire circumferential edge of thecircumferential edge of the second hole edge portion 305 b. That is, thereinforcing portion reinforces the hollow structure by connecting thefirst wall portion 299 and the second wall portion 300.

Note that one reinforcing portion may be provided, or three or morereinforcing portions may be provided. At least one may be provided.Further, the reinforcing portion may be circular or polygonal in a planview. Further, the place to be provided may be anywhere between thefirst installation portion 306 and the second installation portion 307.As shown in FIG. 41B, the reinforcing portion 311 may have a rib wall311 a formed by recessing the second wall portion 300 of the placingportion 297 and connecting (connecting) to the first wall portion 299.In addition, the reinforcing portion may have a rib wall formed byconcaving the first wall portion 299 and connecting (connecting) to thefirst wall portion 299.

As shown in FIG. 42 and FIG. 43 , the first installation portion 306 isa portion in which the first rear mount 50 is provided (inserted). Thefirst installation portion 306 has a third hole edge portion 306 a, afourth hole edge portion 306 b, and a first cylindrical wall 306 c. Thethird hole edge portion 306 a is a circular annular edge portion formedthrough the first wall portion 299 of the placement portion 297. Thethird hole edge portion 306 a is positioned in the interior 5A of thecabin 5 in front of the third seal 291 (sealing material). A front lowerwall 286 a of the rear cross member 286 is positioned above the thirdhole edge portion 306 a. The fourth hole edge portion 306 b is acircular annular edge portion formed through the second wall portion 300of the placement portion 297. The fourth hole edge portion 306 b ispositioned below the third hole edge portion 306 a. The firstcylindrical wall 306 c connects the entire periphery of thecircumferential edge of the third hole edge portion 306 a and the entirecircumferential edge of the circumferential edge of the fourth hole edgeportion 306 b. The first rear mount 50 is inserted through the firstinstallation portion 306 and placed in contact with the beam member 67(support portion). In addition, the first rear mount 50 is attached viaa bolt (stud bolt) 312 and a plurality of nut members 313A and 313Bstanding on the beam member 67 by being screwed into the first threadhole 68.

As shown in FIG. 42 and FIG. 43 , the second installation portion 307 isa portion in which the second rear mount 51 is provided (inserted). Thesecond installation portion 307 also has a third hole edge portion 307a, a fourth hole edge portion 307 b, and a first cylindrical wall 307 c.The third hole edge portion 307 a is a circular annular edge portionformed through the first wall portion 299 of the placement portion 297.The third hole edge portion 307 a is located in the interior 5A of thecabin 5 in front of the third seal 291 (seal material). A front lowerwall 286 a of the rear horizontal member 286 is positioned above thethird hole edge portion 307 a. The fourth hole edge portion 307 b is acircular annular edge portion formed through the second wall portion 300of the placement portion 297. The fourth hole edge portion 307 b ispositioned below the third hole edge portion 307 a. The firstcylindrical wall 307 c connects the entire periphery of thecircumferential edge of the third hole edge portion 307 a and the entirecircumferential edge of the circumferential edge of the fourth hole edgeportion 30 b. The second rear mount 51 is inserted through the secondinstallation portion 307 and placed in contact with the beam member 67(support portion). Further, the second rear mount 51 is attached via thestud bolt 314 and the plurality of nut members 315A and 315B standing onthe beam member 67 by being screwed into the second thread hole 69.

As shown in FIG. 42 and FIG. 43 , the first screw insertion portion 308is a portion through which the first attachment member 316 is inserted.The first attachment member 316 is a member for attaching the placingportion 297 to the beam member 67 (support portion), and is constitutedof bolts. The first screw insertion portion 308 has a fifth hole edgeportion 308 a, a sixth hole edge portion 308 b, and a second cylindricalwall 308 c. The fifth hole edge portion 308 a is a circular annular edgeportion formed through the first wall portion 299 of the placementportion 297. The fifth hole edge portion 308 a is located in theinterior 5A of the cabin 5 at the front of the third seal 291 (sealingmaterial). A front lower wall 286 a of the rear horizontal member 286 ispositioned above the fifth hole edge portion 308 a. The sixth hole edgeportion 308 b is a circular annular edge portion formed through thesecond wall portion 300 of the placement portion 297. The sixth holeedge portion 308 b is positioned below the fifth hole edge portion 308a. The second cylindrical wall 308 c connects the entire periphery ofthe circumferential edge of the fifth hole edge portion 308 a and theentire circumferential edge of the circumferential edge of the sixthhole edge portion 308 b.

A sleeve 317 is provided in the first screw insertion portion 308. Awasher 318 is provided above the sleeve 317. The first mounting member316 is screwed into the third thread hole 70 by inserting the washer 318and the sleeve 317 from above.

As shown in FIG. 42 and FIG. 43 , the second screw insertion portion 309is a portion through which the second attachment member 319 is inserted.The second attachment member 319 is a member for attaching the placingportion 297 to the beam member 67 (support portion), and is constitutedof bolts. The second screw insertion portion 309 also has a fifth holeedge portion 309 a, a sixth hole edge portion 309 b, and a secondcylindrical wall 309 c. The fifth hole edge portion 309 a is a circularannular edge portion formed through the first wall portion 299 of theplacement portion 297. The fifth hole edge portion 309 a is located inthe interior 5A of the cabin 5 in front of the third seal 291 (sealingmaterial). A front lower wall 286 a of the rear horizontal member 286 ispositioned above the fifth hole edge portion 309 a. The sixth hole edgeportion 309 b is a circular annular edge portion formed through thesecond wall portion 300 of the placement portion 297. The sixth holeedge portion 309 b is positioned below the fifth hole edge portion 309a. The second cylindrical wall 309 c connects the entire periphery ofthe circumferential edge of the fifth hole edge portion 309 a and theentire circumferential edge of the circumferential edge of the sixthhole edge portion 309 b.

A sleeve 320 is provided in the second screw insertion portion 309. Awasher 321 is provided above the sleeve 320. The first mounting member316 is screwed into the fourth thread hole 71 by inserting the washer321 and the sleeve 320 from above.

The second mounting member 319 is provided at a distance from the firstmounting member 316 in the machine width direction K2. The firstmounting member 316 and the second mounting member 319 are positionedbetween the first installation portion 306 and the second installationportion 307, and the reinforcing portions 304 and 305 are disposedbetween the first mounting member 316 and the second mounting member319.

Next, the hinge structure 326 supporting the rear bonnet 25 will bedescribed.

As shown in FIG. 44 to FIG. 48 , the hinge structure body 326 has afixed hinge 327, a hinge shaft 328, a movable hinge 329, and a locklever 330. The hinge structure 326 is disposed inside the left side ofthe rear bonnet 25.

As shown in FIG. 44 , the fixing hinge 327 is fixed to the support frame60 (the first leg 64). As shown in FIG. 45 to FIG. 48 , the fixed hinge327 is formed of a plate material and has a vertical wall 327 a, anupper wall 327 b, and a lower wall 327 c. The vertical wall 327 a issuperimposed on the rear surface of the hanging portion 64C of the firstleg 64 and fixed by bolts.

The lower portion of the vertical wall 327 a protrudes rightward fromthe suspended portion 64C, and the lever shaft 331 is fixed to theprojecting portion so as to project rightward. The lever shaft 331 hasan axis extending in the machine width direction K2. The upper wall 327b extends rearward from the upper portion of the vertical wall 327 a.The lower wall 327 c extends rearward from the lower portion of thevertical wall 327 a. And the lower wall 327 c is positioned below theupper wall 327 b.

As shown in FIG. 45 , the hinge shaft 328 extends from the upper wall327 b to the lower wall 327 c in the upward and downward directions. Afixing plate 332 is fixed to the upper end of the hinge shaft 328. Thefixing plate 332 is bolted to the upper wall 327 b.

As shown in FIG. 45 to FIG. 48 , the movable hinge 329 has a rotatingcylinder 333 and a movable piece 334. The rotary cylinder 333 isprovided between the upper wall 327 b of the fixed hinge 327 and therear portion of the lower wall 327 c. A hinge shaft 328 is insertedthrough the rotating cylinder 333. The rotating cylinder 333 is freelyrotatable about the axis of the hinge shaft 328. The movable piece 334is formed of a plate material and has a base wall 334 a, an extendingwall 334 b, and a attaching wall 334 c. One end of the base wall 334 ain a direction along the plate surface and orthogonal to the verticaldirection is fixed to the rotating cylinder 333. Thus, the base wall 334a protrudes radially outward from the rotary cylinder 333. The extendingwall 334 b extends from an end portion of the base wall 334 a in theprojecting direction in a direction intersecting the projectingdirection. The attaching wall 334 c extends from an end of the extendingwall 334 b in the extending direction in a direction opposite to theprotruding direction of the base wall 334 a. As shown in FIG. 44 , anattaching bracket 335 is fixed to the left inner surface of the rearbonnet 25. The extension side of the attaching wall 334 c is fixed tothe attaching bracket 335. That is, the movable hinge 329 is fixed tothe rear bonnet 25. The movable hinge 329 is attached to the fixed hinge327 so as to be rotatable around the longitudinal axis so as to open andclose the rear bonnet 25.

As shown in FIG. 45 to FIG. 48 , the movable piece 334 (movable hinge329) has a locking groove 336. The locking groove 336 is formed in anintermediate portion in the vertical direction of the movable piece 334.In addition, the locking groove 336 is formed continuously over the basewall 334 a, the extending wall 334 b, and the attaching wall 334 c. Thelocking groove 336 is formed by an annular edge formed through themovable piece 334. The locking groove 336 has a first groove portion 336a which is a portion formed on the base portion wall 334 a, a secondgroove portion 336 b which is a portion formed on the extension wall 334b, and a third groove portion 336 c which is a portion formed on theattachment wall 334 c.

As shown in FIG. 45 , FIG. 47 , and FIG. 48 , the width W1 (upper andlower widths) of the locking groove 336 is formed to be the same widthover the length direction of the groove.

As shown in FIG. 46 to FIG. 48 , the lock lever 330 is a member thatmaintains a state in which the rear bonnet 25 is open. The lock lever330 is formed of a plate material whose plate surface faces the machinewidth direction K2 and is long in the front-rear direction. The locklever 330 has a base end portion 330 a (front portion) on the proximalend side, a distal end portion 330 b (rear portion) on the distal endside, and an intermediate portion 330 c between the proximal end portion330 a and the distal end portion 330 b. The base end portion 330 a issupported on the lever shaft 331 so as to be rotatable around the axiscenter. As a result, the locking lever 330 is pivotally supported at thebase end portion 330 a toward the fixed hinge 327 side, and is capableof rocking up and down about the lever shaft 331. In addition, the locklever 330 protrudes rearward from the vertical wall 327 a and passesthrough the locking groove 336. That is, the movable hinge 329 has alocking groove 336 through which the lock lever 330 is inserted.

The distal end portion 330 b is provided with a locking portion 337. Thelocking portion 337 is constituted of a groove in a downward openedstate and is fitted to the lower edge portion (lower edge portion of thefirst groove portion 336 a) of the locking groove 336 in a state wherethe rear bonnet 25 is opened. As a result, rotation of the movable hinge329 is restricted in a state where the rear bonnet 25 is opened. Thatis, the lock lever 330 has a locking portion 337 that restricts therotation of the movable hinge 329 in a state where the rear bonnet 25 isopened by being fitted to the lower edge portion of the locking groove336.

The locking portion 337 has a first groove edge portion 337 a closer tothe base end portion 330 a, a second groove edge portion 337 b opposedto the first groove edge portion 337 a, a first groove edge portion 337a and a second groove edge portion 337 b and a third groove edge portion337 c which connects the upper ends of the first groove edge portions335 c. The second groove edge portion 337 b is formed to be longerdownward than the first groove edge portion 337 a.

As shown in FIG. 48 , in a state in which the locking portion 337 isfitted to the lower edge portion of the locking groove 336, the relationbetween the width W1 in the vertical direction of the locking groove336, the width W2 in the vertical direction of the base end side portion338 which is the portion closer to the base end side of the lock lever330 than the engaging portion 337, the width W3 in the verticaldirection of the tip end side portion 339 which is the portion closer tothe tip end side of the lock lever 330 than the engaging portion 337 isthe width W3>width W1>width W2. That is, the width W2 of the base endside portion 338 is shorter than the width of the locking groove 336,and the width W3 of the tip side portion 339 is longer than the width ofthe locking groove 336 than the locking portion 337.

As shown in FIG. 46 , a grasping member 340 is provided in the middleportion 330 c of the lock lever 330. The grip member 340 protrudesrightward from the right side surface of the lock lever 330. The gripmember 340 may be provided on the base end portion side 330 a of thelock lever 330.

As shown in FIG. 47 , when the rear bonnet 25 is closed, the lowersurface 330 d of the middle portion 330 c of the lock lever 330 contactsthe lower edge portion 336 d (the lower edge portion of the secondgroove portion 336 b) of the locking groove 336. The rear bonnet 25 canmove in the opening and closing direction by the lower surface 330 d ofthe middle portion 330 c of the lock lever 330 sliding on the lower edgeportion 336 d of the locking groove 336. As shown in FIG. 46 , when therear bonnet 25 is closed, as indicated by the solid line, the gripmember 340 is positioned on the left side of the attachment wall 334 c.

As shown in FIG. 46 , when the rear bonnet 25 is opened from the closedstate, the movable hinge 329 moves from the closed position indicated bythe solid line to the open position indicated by the imaginary line. Asshown in FIG. 48 , in a state in which the rear bonnet 25 is opened, thelocking portion 337 coincides with the lower edge portion 336 d (thelower edge portion of the first groove portion 336 a) of the lockinggroove 336, and the locking portion 337 and fits into the lower edgeportion 336 d of the stop groove 336. As a result, movement in theopening and closing direction is regulated in a state where the rearbonnet 25 is opened. When the rear bonnet 25 is opened, the movablehinge 329 is positioned behind the gripping member 340 and can grip thegripping member 340.

To close the rear bonnet 25 from the opened state, hold the grip member340 and pull up the lock lever 330. As shown in FIG. 49 , since thelower end of the base end side portion 338 is located above the loweredge portion 336 d (the lower edge portion of the first groove portion336 a) of the locking groove 336, the movable hinge 329 is inserted intothe rear hood (in a position indicated by a solid line in FIG. 46 ) inthe closing direction of the upper arm 25 (see FIG. 46 ). Thereby, therear bonnet 25 can be closed.

As shown in FIG. 49 , in a state in which the rear bonnet 25 is opened,the lock lever 330 is pulled up and the upper end of the front endportion 330 b abuts against the upper edge portion 336 e (the upper edgeportion of the first groove portion 336 a) of the locking groove 336.Then, the upward swing of the lock lever 330 is restricted. In thisstate, the lower end of the distal end side portion 339 is positionedlower than the upper surface of the lower edge portion 336 d of theengaging groove 336. As a result, the movement of the movable hinge 329in the opening direction of the rear bonnet 25 is regulated by thedistal end side portion 339. That is, the rear bonnet 25 does not movefurther in the opening direction from the position where the movement inthe opening direction is regulated by the lock lever 330.

In the present embodiment, the working machine 1 includes a machine body2, a cabin 5 mounted on the machine body 2, an engine E1 disposed on therear side of the cabin 5, an engine room accommodating the room 5A ofthe cabin 5 and the engine E1 (the bonnet center 24) for separating thecovering member E1 and the covering member E2 from each other. Theworking machine 1 has a covering member (bonnet center 24) of a hollowstructure having a first wall portion 299 disposed on the side of thecabin 5 and a second wall portion 300 arranged on the side of the engineE1, a support part (beam member 67) for supporting the rear part of thecabin 5 arranged on the member, a first rear mount 50 for supporting oneof the rear part of the cabin 5 on the support part, a rear part of thecabin 5, and a second rear mount 51 for supporting the other side of therear portion of the cabin 5 on the supporting portion. The coveringmember includes a first installation portion 306 on which the first rearmount 50 is disposed, a second installation portion 307 on which thesecond rear mount 51 is disposed, a space between the first installationportion 306 and the second installation portion 307, and at least onereinforcing portion (first reinforcing portion 304, second reinforcingportion 305, reinforcing portion 311) which reinforces the hollowstructure by connecting the first wall portion 299 and the second wallportion 300 to each other.

This reinforces the strength of the covering member (the bonnet center25) and prevents the covering member from being recessed by the weightof the cabin 5.

The reinforcing portions 304 and 305 are formed by first hole edgeportions 304 a and 305 a which are edge portions of the through holeformed in the first wall portion 299 and edge portions of the throughhole formed in the second wall portion 300, second hole edge portions304 b and 305 b, and a tubular rib walls 304 c and 305 c connecting thefirst hole edge portions 304 a and 305 a, and the second hole edgeportions 304 b and 305 b. Thereby, the covering member (mounting portion297) can be firmly reinforced. In addition, molding is easy.

Further, it has a sealing material (third seal 291) for sealing betweenthe rear portion of the cabin 5 and the covering member, and thereinforcing portions 304 and 305 are edge portions of the through holeformed in the first wall portion 299, the first hole edge portions 304 aand 305 a and the second hole edge portions 304 b and 305 b which arethe edge portions of the through hole formed in the second wall portion300. The first hole edge portions 304 a and 305 a are seal members (Thethird seal 291) of the cabin 5, and the second hole edge portions 304 band 305 b are closed by the support portion (the beam member 67). Sincethe first hole edges 304 a and 305 a are located in front of the sealant(the third seal 291) and in the interior 5A of the cabin 5, during carwashing or the like, the first hole edges 304 a and 305 a are formed inthe reinforcing portion, thus the water can be prevented from entering.Since the second hole edge portions 304 b and 305 b are closed with thesupport portion (the beam member 67), the sound on the engine room E2side propagates toward the cabin 5 side through the reinforcing portions304 and 305 can be suppressed.

In addition, the reinforcing portions 304 and 305 are elliptical shapeslong in the machine width direction K2. By forming the reinforcingportions 304 and 305 in an oval shape long in the machine directionwidth direction K2, the mounting portion 297 can be effectivelyreinforced.

Further, it has a plurality of reinforcing portions (a first reinforcingportion 304 and a second reinforcing portion 305) provided at intervalsin the machine width direction K2. Thereby, the covering member (placingportion 297) can be effectively reinforced.

Further, the first attachment member 316 for attaching the coveringmember to the support portion (the beam member 67), the attachmentmember for attaching the covering member to the support portion (thebeam member 67), and the attachment member for attaching the coveringmember to the first attachment member 316, and a second attachmentmember 319 provided at an interval from the first attachment member 316.The first attachment member 316 and the second attachment member 319 arepositioned between the first placement portion 306 and the secondplacement portion 307, the portions 304 and 305 are positioned betweenthe first attachment member 316 and the second attachment member 319.Thereby, the covering member (placing portion 297) can be effectivelyreinforced.

The working machine further includes a rear bonnet 25 covering the rearof the engine E1, a fixed hinge 327 fixed to the support frame 60(machine body 2), a fixed hinge 327 fixed to the rear bonnet 25 andopening and closing the rear bonnet 25, a movable hinge 329 mounted soas to be rotatable about a vertical axis, and a lock lever 330 formaintaining a state in which the rear bonnet 25 is opened. The movablehinge 329 has a locking groove 336 through which the lock lever 330 isinserted. The locking lever 330 has a base end 330 a pivotally supportedon the fixed hinge 327 side so as to be swingable about a lateral axisand is fitted to the lower edge 336 d of the locking groove 336 so thatthe movable hinge 329 and a locking portion 337 for restricting therotation of the lever. In a state in which the locking portion 337 isfitted to the lower edge portion 336 d of the locking groove 336, thelock lever 330 has a width W2 in the vertical direction of the base endside portion 338, which is a portion on the base end side from thelocking portion 337 is smaller than the width W1 in the verticaldirection of the locking groove 336 and the width W3 in the verticaldirection of the front end portion 339 which is a portion on the tipside of the locking portion 337 is larger than the vertical width W1 ofthe locking groove 336.

When the rear bonnet 25 is opened, when the lock lever 330 is pulled upand the upper end abuts against the upper edge of the locking groove336, the upward swing of the lock lever 330 is restricted. In thisstate, the lower end of the distal end side portion 339 is positionedlower than the upper surface of the lower edge portion of the engagementgroove 336. As a result, the movement of the movable hinge 329 in theopening direction of the rear bonnet 25 is regulated by the distal endside portion 339. That is, the rear bonnet 25 does not move further inthe opening direction from the position where the movement in theopening direction is restricted by the lock lever 330, and it ispossible to prevent the rear bonnet 25 from being excessively opened.

Next, the supporting structure of the oil cooler O1 will be described.

As shown in FIG. 50 , a partition member 341 is provided on the upperportion of the third leg 66 of the support frame 60. The partitionmember 341 constitutes a part of a partition that partitions thearrangement side of the engine E1 and the arrangement side of theradiator R1 and the oil cooler O1. The partition member 341 is fixed toa fixing plate 342 attached to the third leg 66. A shroud 343 coveringthe cooling fan is provided below the partition member 341. A radiatorR1 is disposed outside (right) the shroud 343. A support frame 344 isattached to the radiator R1.

As shown in FIG. 51 , the support frame 344 includes an upper frame 345,a lower frame 346 disposed below the upper frame 345, and a second frame345 that connects one ends (front end portions) of the upper frame 345and the lower frame 346, the first vertical frame 347 and a secondvertical frame 348 connecting the other ends (rear end portions) of theupper frame 345 and the lower frame 346.

As shown in FIG. 50 , the upper frame 345 is provided on the upper sideof the radiator R1. The upper frame 345 has a main frame portion 349provided along the upper portion of the radiator R1. As shown in FIG. 52, the main frame portion 349 has a side wall 350 and an upper wall 351.

As shown in FIG. 50 , the side wall 350 is provided along the right sideportion of the upper portion of the radiator R1. The front portion ofthe side wall 350 is fixed to the radiator R1 by bolts 365A and the rearportion thereof is fixed to the radiator R1 by bolts 365B. That is, theupper part of the radiator R1 is fixed to the upper frame 345.

As shown in FIG. 52 , the upper wall 351 has a first portion 351 aextending from the front portion of the side wall 350 toward the insideof the body (leftward), a first portion 351 a extending from the rearportion of the side wall 350 toward the inside of the machine (leftward)And a second portion 351 b to be formed. The upper wall 351 is locatedabove the radiator R1 (see FIG. 50 ). At a front portion of the firstportion 351 a, a first extending portion 352 extending inward of themachine body is provided. A first stay portion 353 extends upward fromthe extending end portion of the first extending portion 352. The firststay portion 353 is fixed to a boss portion 388 provided on thepartition member 341 by a bolt 354A.

On the rear portion of the second portion 351 b, a second extendingportion 355 extending inward of the machine body is provided. A secondstay portion 356 extends upward from the extending end portion of thesecond extending portion 355. The second stay portion 356 is fixed to aboss portion 389 provided on the partition member 341 by a bolt 354B.The upper frame 345 is attached to the support frame 60 by the firststay portion 353 and the second stay portion 356.

As shown in FIG. 50 , the lower frame 346 is provided on the lower sideof the radiator R1. As shown in FIG. 51 , the lower frame 346 has afirst wall 346 a, a second wall 346 b, a third wall 346 c, a fourth wall346 d, and a fifth wall 346 e. As shown in FIG. 50 , the first wall 346a is provided along the right side portion of the lower portion of theradiator R1. The front portion and the rear portion of the first wall346 a are fixed to the radiator R1 by bolts 385A and 385B. As a result,the lower frame 346 is fixed to the lower part of the radiator R1. Thelower part of the radiator R1 is supported by a mounting member 359provided on the turn frame 54 via vibration isolating members 358(rubber) (see FIGS. 3 and 7 ). Thereby, the lower frame 346 is supportedon the side of the machine body 2 via the radiator R1.

The second wall 346 b extends from the front end of the first wall 346 atoward the inside of the airframe. The third wall 346 c extends rearwardfrom the extended end of the second wall 346 b. The fourth wall 346 dextends toward the inside of the airframe from the rear end of the firstwall 346 a. The fifth wall 346 e extends rearward from the extended endof the fourth wall 346 d.

The upper frame 345 is attached to the support frame 60, and the lowerframe 346 is supported on the side of the machine body 2 via theradiator R1, so that the support frame 344 is supported on the machinebody 2 side.

As shown in FIG. 51 , the first vertical frame 347 is formed in avertically elongated band plate shape, and its plate surface facesforward and backward. The upper part of the first vertical frame 347 isfixed to the side wall 350 and the upper wall 351 (the first part 351 a)of the upper frame 345, and the lower part thereof is fixed to thesecond wall 346 b of the lower frame 346. A first pivotally supportingportion (pivotally supporting portion) 360 projecting outwardly of themachine body is provided in the lower portion of the first verticalframe 347.

As shown in FIG. 53 , the first pivot support portion 360 is formed in ahook shape that opens upward, and has a first engagement groove(engagement groove) 361 that opens upward. The first engagement groove361 has a first bottom portion (bottom portion) 361 a, a first guidesurface (guide surface) 361 b, and a first longitudinal surface(longitudinal surface) 361 c. The first bottom portion 361 a is formedin a downwardly concave curved shape. A pivot 362 provided at a lowerportion of the oil cooler O1 is supported on the first bottom portion361 a so as to be rotatable about an axis center. The first guidesurface 361 b is an end portion of the first bottom portion 361 a andextends upward from an end portion on the base side of the first pivotsupport 360 (an end on the inner side of the body). In addition, thefirst guide surface 36 b is an inclined surface that is inclined so asto move away from the radiator R1 as it goes downward, and the lowerportion is an inclined surface continuing to the first bottom portion361 a. The first longitudinal face 361 c is an end portion of the firstbottom portion 361 a and extends upward (substantially in the verticaldirection) from the end portion (the end portion on the outer side ofthe machine body) of the first pivot support portion 360 on the sideopposite to the base side thereof.

As shown in FIG. 51 , the second vertical frame 348 is formed in avertically long band plate shape, and the plate surface faces forwardand backward. In the second vertical frame 348, the upper part is fixedto the side wall 350 and the upper wall 351 (the second part 351 b) ofthe upper frame 345, and the lower part is fixed to the fourth wall 346d of the lower frame 346. A second pivotally supporting portion(pivotally supporting portion) 363 projecting outwardly of the machinebody is provided under the second vertical frame 348.

As shown in FIG. 53 , the second pivot support portion 363 is formed ina hook shape that opens upward, and has a second engagement groove(engagement groove) 364 formed in an open state at the upper side. Thesecond engagement groove 364 has a second bottom portion (bottomportion) 364 a, a second guide surface (guide surface) 364 b, and asecond vertical surface (longitudinal surface) 364 c. The second bottomportion 364 a is formed in a downwardly concave curved shape. A pivot362 is also rotatably supported on the second bottom 364 a around theaxis center. The second guide surface 364 b is an end portion of thesecond bottom portion 364 a and extends upward from an end portion onthe base side of the second pivot support 363 (an end on the inner sideof the body). Further, the second guide surface 364 b is an inclinedsurface that is inclined to move away from the radiator R1 as it goesdownward and the lower portion is an inclined surface continuing to thesecond bottom portion 364 a. The second longitudinal face 364 c is anend portion of the second bottom portion 364 a and extends upward(substantially in a vertical direction) from an end portion on the sideopposite to the base portion side of the second pivot support portion363 (an end portion on the outer side of the machine body).

The pivotal portion pivotally supporting the pivot 362 includes a firstpivot portion 360 provided in the first vertical frame 347 and a secondpivot portion 363 provided in the second vertical frame 348.

As shown in FIG. 50 , the upper portion of the shroud 343 is bolted tothe first stay portion 353 and the second stay portion 356. The lowerportion of the shroud 343 is bolted to the third wall 346 c and thefifth wall 346 e. Thus, the support frame 344 supports the shroud 343.

As shown in FIG. 51 and FIG. 53 , a first lower bracket 366, a secondlower bracket 367, and a third lower bracket 368 are provided on thelower (lower end face) of the oil cooler O1. The first lower bracket 366is provided near the front portion from the center portion in the frontand rear of the oil cooler O1. The second lower bracket 367 is providedcloser to the rear part from the center part in the front and rear ofthe oil cooler O1. The front portion of the third lower bracket 368 isfixed to the first lower bracket 366 by a bolt 390A. The rear portion ofthe third lower bracket 368 is fixed to the second lower bracket 367 bybolts 390B.

A pivot 362 having an axis extending in the front-rear direction K1 isfixed to the third lower bracket 368. The center of the pivot 362 in thefront-rear direction K1 is fixed to the third lower bracket 368 andprotrudes frontward and rearward from the third lower bracket 368. Thefront portion of the pivot 362 is inserted into the first engagementgroove 361 of the first pivot support 360 from above. That is, the pivot362 is rotatably fitted around the axis center on the first bottomportion 361 a of the first engagement groove 361. Further, the rearportion of the pivot 362 is inserted into the second engagement groove364 of the second pivot support 363 from above. That is, the pivot 362is rotatably fitted around the axis center on the second bottom 364 a ofthe second engagement groove 364. In other words, the pivot 362 isprovided in the lower part of the oil cooler O1 (heat exchanger) and ispivotally supported by the first pivot support 360 (the first bottom 361a) and the second pivot support 363 (the second bottom 364 a).

As shown in FIG. 53 , a first regulating member 369 is provided at thefront portion of the pivot 362. The first regulating member 369 isformed in the shape of a ring disk, and is fitted over and fixed to thepivot 362. The first regulating member 369 restricts the forwardmovement of the pivot 362 (oil cooler O1) by contacting the rear surfaceof the first pivot support 360. A second regulating member 370 isprovided at the rear portion of the pivot 362. The first regulatingmember 369 is formed in the shape of a ring disk, and is fitted over andfixed to the pivot 362. The second regulating member 370 abuts againstthe front surface of the second pivot support 363, thereby restrictingthe rearward movement of the pivot 362 (oil cooler O1).

With the above configuration, the lower part of the oil cooler O1 ispivotally supported by the support frame 344 (the first pivot support360, the second pivot support 363) so that the upper part moves towardand away from the radiator R1. As a result, the oil cooler O1 moves inthe opposite position 371 (see the imaginary line in FIG. 54 ), which isthe state facing the radiator R1, and the oil cooler O1 separates fromthe radiator R1 around the first pivot support 360 and the second pivotsupport 363 and a tilting posture 372 (see the solid line in FIG. 54 )in a state of being tilted in the direction.

As shown in FIGS. 51 and 52 , a first upper bracket 373 and a secondupper bracket 374 are provided on the upper portion (upper end surface)of the oil cooler O1. The first upper bracket 373 is provided at thefront portion of the oil cooler O1. The first upper bracket 373 isprovided with a first attachment piece portion 373 a. The second upperbracket 374 is provided at the rear portion of the oil cooler O1. Thesecond upper bracket 374 is provided with a second attachment pieceportion 374 a.

As shown in FIG. 51 and FIG. 52 , attachment members 376 made of a platematerial are attached to the first attachment piece portion 373 a andthe second attachment piece portion 374 b. That is, the mounting member376 is attached to the upper part of the oil cooler O1 (heat exchanger).

As shown in FIG. 52 , the mounting member 376 has a first wall portion376 a, a second wall portion 376 b, and a third wall portion 376 c. Thefirst wall portion 376 a is disposed laterally with the plate surfacefacing upward and is disposed between the first attachment piece portion373 a and the second attachment piece portion 374 b. The second wallportion 376 b extends upward from the front portion of the first wallportion 376 a. The front portion of the second wall portion 376 b issuperimposed on the first attachment piece portion 373 a and fixed tothe first attachment piece portion 373 a with bolts 391A (see FIG. 50 ).The third wall portion 376 c extends upward from the rear portion of thefirst wall portion 376 a. The rear portion of the third wall portion 376c is superimposed on the second attachment piece portion 374 b and fixedto the second attachment piece portion 374 b by a bolt 391B (see FIG. 50).

As shown in FIG. 52 , the attachment member 376 is provided with ahandle 376 d. The handle 376 d includes a root portion 376 e extendingoutward from the center of an end portion of the first wall portion 376a on the outer side of the machine body and a base portion 376 eextending from the extending end of the base portion 376 e to a gripportion 376 f, and a grip cover 376 g covering the grip portion 376 fThe first wall portion 376 a is located above the upper surface of theoil cooler O1, and the grip portion 376 f protrudes to the lateral sideof the oil cooler O1 outside the machine body.

A fixing member 377 is fixed to the center of the upper surface of thefirst wall portion 376 a in the front-rear direction of the machinebody. The fixing member 377 is located on the front side of the rootportion 376 e of the handle 376 d. The fixing member 377 is formed in arectangular block shape, and a thread hole 378 is formed on the rearside of the upper portion.

As shown in FIG. 51 and FIG. 52 , a guide member 379 made of a platematerial is provided on the support frame 344 (upper frame 345). Thebase end of the guide member 379 is fixed to the main frame portion 349of the upper frame 345 and protrudes outward from the main frame portion349. That is, the guide member 379 protrudes from the support frame 344toward the side where the oil cooler O1 is tilted. The guide member 379has a guide groove 380. The guide groove 380 is a long groove long inthe protruding direction (the machine width direction K2) of the guidemember 379. The guide groove 380 is formed closer to the machine outwarddirection from the center of the guide member 379 in the machine widthdirection K2. The guide groove 380 is formed by an annular edge portionformed to penetrate the guide member 379 in the front-rear direction.

As shown in FIG. 55 , the guide groove 380 has a first guide portion 381on the proximal end side of the guide member 379 and a second guideportion 382 on the distal end side of the guide member 379. The firstguide portion 381 is formed to be shorter than the second guide portion382. The first guide portion 381 and the second guide portion 382 areformed continuously. The first guide portion 381 is formed in aninclined direction which is shifted upward in the projecting directionfrom the base end in the projecting direction of the guide member 379.The second guide portion 382 is formed in an inclined direction thatmoves downward as going from the first guide portion 381 to the tipportion in the projecting direction.

As shown in FIGS. 51 and 52 , a fixing member 383 for fixing the fixingmember 377 to the guide member 379 is provided. The fixture 383 isconstituted of one bolt. It is to be noted that a plurality of fixingmembers 383 and a plurality of guide members 379 may be provided. Thefixture 383 has a head portion 383 a and a screw shaft portion 383 b.The screw shaft portion 383 b is inserted through the washer 384.Further, the screw shaft portion 383 b passes through the guide groove380 and is screwed into the thread hole 378 of the fixing member 377.That is, the fixture 383 is threaded to the fixing member 377 by passingthrough the guide groove 380. The shape of the head portion 383 a is notparticularly limited, and may be, for example, a hexagonal bolt shape, athumb screw shape, or the like.

As shown in FIG. 55 , the screw shaft portion 383 b of the fixture 383is movable in the guide groove 380 in the longitudinal direction of thegroove. The fixing member 377 and the fixing member 383 are disposed ata first position 386 (see imaginary line) where the screw shaft portion383 b is located at the base end of the guide groove 380 and a secondposition 386 b at which the screw shaft portion 383 b is positioned atthe tip of the guide groove 380 (see the solid line). In a state inwhich the fixing member 377 and the fixing member 383 are located at thefirst position 386, the oil cooler O1 is set to the opposing attitude371 indicated by a virtual line. In a state where the fixing member 377and the fixing member 383 are positioned at the second position 387, theoil cooler O1 is in the tilting attitude 372 indicated by the solidline. As described above, the guide groove 380 has a first position 386,which is a position where the oil cooler O1 faces the radiator R1(opposing position 371), a first position 386 in which the oil cooler O1is tilted in a direction away from the radiator R1 around the pivotsupport portion And the second position 387 which is the position of thefixing member 377 (the tilting posture 372). The proximal end 381 a ofthe first guide portion 381 holds the fixing member 377 and the fixingmember 383 at the first position 386 and the distal end portion 382 a ofthe second guide portion 382 holds the fixing member 377 and the fixingmember 383 at the second position.

The length of the first guide portion 381 (the depth from the connectionportion on the lower side of the first guide portion 381 and the secondguide portion 382 to the bottom portion when the oil cooler O1 isarranged in the opposing posture) is fixed may be longer than the radiusof the screw shaft portion 383 b of the tool 383. Accordingly, when theoil cooler O1 is disposed in the opposing posture, the position of thecenter of gravity of the screw shaft portion 383 b is lower than theconnection portion on the lower side of the first guide portion 381 andthe second guide portion 382, so that the fixture 383 can be reliablyheld in the first position 386.

When the oil cooler O1 is normally used, the oil cooler O1 is set in theopposing posture 371, and the fixture 383 is fastened to the fixingmember 377 at the first position 386 to fix the oil cooler O1 in theopposing posture 371.

When checking clogging of the fins of the radiator R1 and cleaning thefins, fixation of the fixture 383 to the fixing member 377 is released(loosened). Thereafter, grasp the handle 376 d and pull the oil coolerO1 downward in a direction away from the radiator R1 while pulling upthe oil cooler O1. When the screw shaft portion 383 b of the fixture 383gets over the convex portion at the boundary between the first guideportion 381 and the second guide portion 382, the screw shaft portion383 b is guided by the second guide portion 382 on the descending slope,and the second position 387. By holding the fixture 383 in the secondposition 387, the oil cooler O1 is held in the tilted posture 372. Theoperation of changing the position of the oil cooler O1 can be performedin a short time by loosening a single bolt (fixture 383), so that themaintenance work of the radiator R1 can be shortened.

In the present embodiment, the working machine 1 includes a machine body2, a radiator R1 mounted on the machine body 2, a heat exchanger (oilcooler O1) arranged to face the radiator R1, a heat exchanger (oilcooler O1 at least one pivotally supporting portion (a first pivotallysupporting portion 360, a second pivotally supporting portion 363)pivotally supporting a lower portion of the support frame 344 in arotatable manner around a lateral axis, a support frame 344 forsupporting the upper portion of the heat exchanger, a guide member 379having a guide groove 380, a fixing member 377 provided at the upperportion of the heat exchanger (oil cooler O1), a fixing member 370inserted through the guide groove 380 and screwed to the fixing member377 and a tool 383. The guide groove 380 has a first position 386 wherethe heat exchanger (oil cooler O1) faces the radiator R1 and a secondposition 386 where the upper portion of the heat exchanger (oil coolerO1) is tilted in a direction away from the radiator R1 around the pivotsupport portion and guides the fixing member 377 between the position387.

According to this configuration, when the fixing of the fixing member383 to the fixing member 377 is released at the first position 386 andthe heat exchanger is tilted in a direction away from the radiator R1around the pivot portion, the fixing member 377 (and the fixing member388) is guided from the first position 386 to the second position 387 bythe guide groove 380. In addition, by holding the fixing member 377 (andthe fixing member 383) in the second position 387 by the guide groove380, the heat exchanger is held in a state of being inclined in adirection away from the radiator R1. This makes it easy to hold thestate in which the heat exchanger is tilted.

Further, only one fixture 383 is provided, and by switching the state ofscrewing of one fixing member 377, it is possible to switch between astate of restraining the movement of the fixing member 377 along theguide groove 380 and a state of permitting the movement of the fixingmember 377.

According to the above configuration, since the heat exchanger can betilted simply by loosening the fixture 383 by one, it is possible toeasily perform the operation of tilting the heat exchanger.

The guide member 379 protrudes from the support frame 344 toward theside where the heat exchanger (oil cooler O1) tilts, and the guidegroove 380 is formed so as to protrude from the support frame 344 in adirection in which the guide member 379 protrudes from the support frame344, a first guide portion 381 which is formed in an inclined directionwhich moves upward in the direction of protrusion from the first guideportion 381 and a second guide portion 381 which is formed in aninclined direction which moves downward from the first guide portion 381toward the tip portion in the projecting direction. The proximal end 381a of the first guide portion 381 holds the fixture 383 at the firstposition 386 and the distal end portion 382 a of the second guideportion 382 holds the fixture 383 at the second position 387.

According to this, since the first guide portion 381 of the guide groove380 is inclined so as to move upward from the base end in the protrudingdirection, in the first position 386, the fixing of the fixing member383 to the fixing member 377 is released, the heat exchanger will notfall accidentally. Further, at the first position 386, it is unnecessaryto hold the heat exchanger when releasing the fixing of the fixingmember 383 to the fixing member 377. Further, since the second guideportion 382 has an inclined shape that moves downward as it goes fromthe first guide portion 381 to the tip portion in the projectingdirection, the heat exchanger inadvertently moves toward the radiator R1from the inclined state can be prevented.

Further, the working machine has a pivot shaft 362 which is provided ata lower portion of the heat exchanger (oil cooler O1) and is pivotallysupported by the first pivot support portion 360 and the second pivotsupport portion 363, and includes a first pivot support portion 360, asecond pivot portion 360. The pivotally supporting portion 363 is formedin an upwardly opened shape and has a first engaging groove 361 and asecond engaging groove 364 into which the pivot 362 is inserted fromabove. The first engagement groove 361 and the second engagement groove364 include a first bottom portion 361 a and a second bottom portion 364a into which the pivot 362 is rotatably fitted around the axis centerand a slope and the lower portion has a first guide surface 361 b and asecond guide surface 364 b continuous with the first bottom portion 361a and the second bottom portion 364 a.

According to this, when inserting the pivot 362 from above into thefirst engaging groove 361 and the second engaging groove 364, the pivot362 is guided by the first guide surface 361 b and the second guidesurface 364 b and is engaged with the first engagement, it can be easilyinserted into the first bottom portion 361 a of the groove 361 and thesecond bottom portion 364 a of the second engagement groove 364.Accordingly, it is easy to pivotally support the lower portion of theheat exchanger to the first pivot support portion 360 and the secondpivot support portion 363.

The support frame 344 includes an upper frame 345 which is provided onthe upper side of the radiator R1 and to which the upper part of theradiator R1 is fixed and which is attached to the support frame 60, alower frame 346 provided on the lower side of the radiator R1 and fixedto the lower part of the radiator R1, a first vertical frame 347connecting one end portions of the upper frame 345 and the lower frame346, and an upper frame 345 and a lower frame and a second verticalframe 348 that connects the other end portions of the first verticalframe 346 and the second vertical frame 346. The guide member 379 isprovided on the upper frame 345 and the pivot support portion isprovided on the first pivot support 360 and a second pivotallysupporting portion 363 provided in the second vertical frame 348.

Thereby, the support frame 344 can be firmly structured.

Further, it includes a mounting member 376 attached to the upper part ofthe heat exchanger (oil cooler O1) and fixing the fixing member 377, anda handle 376 d provided on the mounting member 376. By having the handle376 d, it is easy to change the posture of the heat exchanger. Further,to simplify the structure, the fixing member 377 and the handle 376 dare provided on the mounting member 376 attached to the upper part ofthe heat exchanger, that is, the fixing member 377 and the handle 376 dare provided on the same member.

In addition, there are a machine body 2, a radiator R1 mounted on themachine body 2, a heat exchanger (oil cooler O1) arranged to face theradiator R1, a lower portion of the heat exchanger O1 rotatable about atransverse axis at least one pivot support portion (first pivot supportportion 360, second pivot support portion 363) that supports the heatexchanger O1, a support frame 344 that supports the upper portion of theheat exchanger O1, a fixture 383 that fixes the heat exchanger O1 to thesupport frame 344 and has only one fixture 383. The fixture 383 releasesthe state of fixing the heat exchanger O1 to the support frame 344 andthe fixation to the support frame 344 to tilt the heat exchanger O1tiltable And the state to be switched.

In the present embodiment, the fixing member 377 is provided to the heatexchanger O1, the fixing member 383 is inserted into the guide groove380 of the guide member 379 fixed to the support frame 344, and screwedto the fixing member 377, whereby heat exchange The structure in whichthe container O1 is fixed to the support frame 344 has been described,but the present invention is not limited to this. For example, a fixingmember 377 is provided on one side of the support frame 344 or the heatexchanger O1, and an insertion portion (for example, a hole portion or aU-groove or the like) for inserting the fixing member 383 is provided onthe other, and the fixing member 383 is inserted through the insertionportion and may be attached to the fixing member 377.

Next, the floor mat 32 will be described.

As shown in FIG. 6 and FIG. 56 , the front lower frame 52 of the cabin 5has a front horizontal member (horizontal member) 396, a first frontassembling portion 397, and a second front assembling portion 398. Thefront cross member 396 is provided between the lower end portions of thefirst front pillar portion 77 and the second front pillar portion 78.The first front assembling portion 397 is formed of a plate material andis provided on the lower left side of the front transverse member 396.The first front mount 48 is assembled to the first front assemblingportion 397. The second front assembling portion 398 is formed of aplate material and is provided at the lower right portion of the fronttransverse member 396. A second front mount 49 is assembled to thesecond front assembling portion 398.

As shown in FIG. 57 and FIG. 61 , the front lateral member 396 is formedinto an odd-shaped tube body, for example, by extruded steel. The frontcross member 396 has a front wall 399, a rear wall 400, an upper wall401, an intermediate wall 402, a first lower wall 403, a second lowerwall 404, and an extension wall 405. The front wall 399 is located inthe outdoor 5B of the cabin 5, and the rear wall 400 is located in theroom 5A of the cabin 5. The rear wall 400 has an upper portion 400 a anda lower portion 400 b. The upper and lower widths of the upper portion400 a are narrower than the upper and lower widths of the lower portion400 b. In addition, the rear wall 400 is formed in a stepped shape inwhich the upper portion 400 a is closer to the interior 5A than thelower portion 400 b. Accordingly, the rear wall 400 has a step portion400 c between the upper portion 400 a and the lower portion 400 b. Theinterior 5A side of the upper portion 400 a and the lower portion 400 bis formed as a flat surface.

The upper wall 401 connects upper end portions of the front wall 399 andthe rear wall 400. An upwardly open groove portion 406 is provided inthe middle portion of the upper wall 401. The lower end of thewindshield 407 is inserted into the groove 406 together with the sealant408. The intermediate wall 402 is provided between the front wall 399and the rear wall 400. Further, the intermediate wall 402 is providedcloser to the front wall 399. The first lower wall 403 connects thefront wall 399 and the lower end of the intermediate wall 402 andprojects rearward from the intermediate wall 402. The second lower wall404 is positioned above the first lower wall 403 and connects the lowerportion of the intermediate wall 402 and the lower end of the rear wall400. The extension wall 405 extends downward from the lower end of thefront wall 399.

As shown in FIG. 57 and FIG. 61 , the first front assembling portion 397is inserted and fixed between the first lower wall 403 and the secondlower wall 404. The first front assembling portion 397 protrudesrearward from the lower end of the rear wall 400. The first front mount48 includes a first vibration isolating member (rubber) 409, a secondvibration isolating member (rubber) 410, a holding plate 411, and abacking plate 412. The first damping member 409 is positioned on theupper side of the first front assembling portion 397 and the seconddamping member 410 is located on the lower side of the first frontassembling portion 397. The pressing plate 411 is positioned on theupper surface of the first vibration isolating member 409, and thebacking plate 412 is positioned on the lower surface of the first frontassembling portion 397. The first front mount 48 is assembled to thefirst mount attachment portion 72 and the first front attachment portion397 by a bolt (stud bolt) 413, a first nut 414, a second nut 415, and athird nut 416. The bolt 413 passes through the first front mount 48 andthe first mount attachment portion 72 in the up and down direction. Thefirst nut 414 is threadedly engaged with the lower end side of the bolt413. The second nut 415 and the third nut 416 are screwed to the upperpart of the bolt 413.

Similarly to the first front assembling portion 397, the second frontassembling portion 398 is inserted and fixed between the first lowerwall 403 and the second lower wall 404. Further, since it is configuredsimilarly to the second front mount 49, description thereof is omitted.

As shown in FIG. 57 and FIG. 61 , a first cutout portion (openingportion) 417 is formed in the left portion of the front horizontalmember 396 and corresponding to the first front mount 48. The firstcutout portion 417 is an opening edge portion formed by cutting out thefront cross member 396 so that the front lateral member 396 does notinterfere with the first front mount 48. That is, the front cross member396 has an opening (covering-target portion) formed by cutting out aportion corresponding to the first front mount 48 (front mount member).The first cutout portion 417 is formed continuously from the upperportion 400 a (a position above the step portion 400 c) of the rear wall400 to the front end of the second lower wall 404. The front portion ofthe first vibration isolating member 409, the front portion of theholding plate 411, the front portions of the second nut 415 and thethird nut 416 are located in the first cutout portion 417.

As shown in FIG. 56 , a second cutout (opening) 418 is provided in theright part of the front lateral member 396 and corresponding to thesecond front mount 49. The second cutout portion 418 is an opening edgeportion formed by cutting the front cross member 396 so that the frontlateral member 396 does not interfere with the second front mount 49.That is, the front cross member 396 has an opening (covering-targetportion) formed by cutting out a portion corresponding to the secondfront mount 49 (front mount member). The configuration of the secondcutout 418 is configured substantially similar to the first cutout edge417.

As shown in FIG. 56 , a floor portion 419 is provided behind the frontlower frame 52. The floor portion 419 is formed by combining a pluralityof plate materials and is attached to the front portion of the turnframe 54 shown in FIG. 7 . As shown in FIG. 4 , the floor portion 419 isprovided between the seat base 31 and the front lower frame 52 of themachine body 2. As shown in FIG. 58 , a floor mat 32 is laid on thisfloor portion 419.

The floor mat 32 is provided between the lower end of the seat base 31and the lower end of the front lower frame 52 of the machine body 2.

As shown in FIG. 58 and FIG. 59 , the floor mat 32 has a mat main body420, a first covering portion 421, and a second covering portion 422.The mat main body 420, the first covering portion 421, and the secondcovering portion 422 are integrally formed with an elastic member suchas rubber. The floor mat 32 is molded by a mold (metal mold). The matmain body 420 is a part laid almost over the entire area of the floorpart 419. The first covering portion 421 is provided on the left side ofthe front portion of the mat main body 420. The first covering portion421 corresponds to the first cutout portion 417, and is a portion thatcovers (closes) the first cutout portion 417 from the side of the room5A. That is, the first cutout portion 417 (cutout portion) is a coveringtarget portion which is covered (blocked) by the first covering portion421. The second covering portion 422 is provided on the right side ofthe front portion of the mat main body 420. The second covering portion422 corresponds to the second cutout portion 418 and is a portion thatcovers (closes) the second cutout portion 418 from the side of the room5A. That is, the second cutout portion 418 (cutout portion) is acovering target portion which is covered (blocked) by the secondcovering portion 422.

The solid lines in FIG. 64 and FIG. 65A show the state of the firstcovering portion 421 in a state in which the floor mat 32 is not laid onthe floor portion 419. In a state where the floor mat 32 is not laid onthe floor portion 419, the first covering portion 421 is in a stateshown by solid lines in FIG. 64 and FIG. 65A. The first covering portion421 and the second covering portion 422 are raised upward so that thefloor mat 32 is disposed on the floor portion 419, and the floor mat 32is laid on the floor portion 419.

58 and 60, in a state in which the floor mat 32 is laid on the floorportion 419, the first covering portion 421 and the second coveringportion 422 are formed by the front cross member 396 (the lower portionof the front surface portion 40 of the cabin 5) and is held in a raisedstate. Thus, FIG. 59 , FIG. 62 , and FIG. 63 show a state in which thefloor mat 32 is laid on the floor portion 419.

As shown in FIG. 59 , a first forward-placing portion 423L is providedon the machine outward direction of the first covering portion 421. Asecond forward-placing portion 424L is provided on the inner side of thefirst covering portion 421 in the machine body. The firstforward-placing portion 423R is also provided on the outer side of thesecond covering portion 422 on the machine body. A secondforward-placing portion 424R is also provided on the inboard side of thesecond covering portion 422.

As shown in FIG. 63 , the first forward-placing portion 423L is placedon the first front assembling portion 397. The second forward-placingportion 424L is placed on the floor portion 419. Further, the firstforward-placing portion 423R is placed on the second front assemblingportion 398. The second forward-placing portion 424R is placed on thefloor portion 419.

Since the configuration of the second covering portion 422 is the sameas that of the first covering portion 421, in the following description,the first covering portion 421 will be described and the description ofthe second covering portion 422 will be omitted.

FIG. 62 to FIG. 65B, the first covering portion 421 includes a firstcover wall portion 426, a hinge portion 427, a second cover wall portion428, a third cover wall portion 429, a connecting wall portion 430, anda reinforcing rib wall 431.

As shown in FIG. 64 , the first cover wall portion 426 is formed in arectangular plate shape. The first cover wall portion 426 has a sideportion (a rear edge portion) 426 a connected to the mat main body 420,another side portion 426 b opposed to the one side portion 426 a, and asecond cover wall portion 426 b extending in a direction along the oneside portion 426 a and two opposed side portions (a first opposing sideportion 426 c and a second opposing side portion 426 d) opposed to eachother with a space therebetween. One of these two opposed side portions(the outer side of the machine body body) is referred to as a firstopposing side portion 426 c, and the other (the inner side of themachine body) is referred to as a second opposing side portion 426 d.

As shown in FIG. 65A, one side portion 426 a is connected to the matmain body 420 via a hinge portion (connecting portion) 427. The mat mainbody 420 is provided with a rising wall 420 b rising from the frontportion of the bottom wall 420 a. At the upper end of the rising wall420 b, an extending wall 420 c extending forward is provided. The hingeportion 427 connects the extension wall 420 c and one side portion 426 aof the first cover wall portion 426. The upper surface of the hingeportion 427 and the upper surface of the first cover wall portion 426are flush with the upper surface of the extending wall 420 c (the sameheight).

As shown in FIG. 59 , the height of the extending wall 420 c is the sameas the height of the first forward-placing portion 423L and 423R, thesecond forward-placing portion 424L and 424R, the rear rising from thetrailing edge of the bottom wall 420 a of the mat main body 420 and theheight of the side rising portion 420 e rising from the right side edgeof the bottom wall 420 a of the mat main body 420. Thus, at the time ofmolding the floor mat 32, the heights of the first covering portion 421and the second covering portion 422 are the same as the height of themat main body 420. That is, even if the first covering portion 421 andthe second covering portion 422 are provided, the total thickness(overall dimension in the vertical direction) of the floor mat 32 is notchanged.

As shown in FIG. 65A, the thickness D1 of the hinge portion 427 isthinner than the thickness D2 of the extending wall 420 c, and isthinner than the thickness D3 of the first cover wall portion 426. Thatis, the hinge portion 427 has a structure that is easily elasticallydeformed at the hinge portion 427. In this manner, the first coveringportion 421 is bent at the intended portion (the hinge portion 427).

In addition, as shown in FIG. 64 , the first opposing side portion 426 cis separated apart from the first forward-placing portion 423L, thesecond opposing side portion 426 d is separated from the secondforward-placing portion 424L. Thus, when the first cover wall portion426 is lifted up, the hinge portion 427 elastically bends as shown by animaginary line in FIG. 65A, and the first cover wall portion 426 isswung upward. That is, the hinge portion 427 is elastically bendable soas to swing the first cover wall portion 426 upward.

As shown in FIG. 62 , FIG. 63 , FIG. 65 A, and FIG. 65 B, the secondcover wall portion 428 extends downward from the first opposing sideportion 426 c. The shape of the projecting end portion 428 a which is anend portion of projecting side of the second cover wall portion 428 isformed to have a shape being approximately same with the shape of theupper portion of the rear wall 400 of the front lateral member 396. Thethickness D4 of the second cover wall portion 428 is formed to bethicker than the thickness D3 of the first cover wall portion 426 (referto FIG. 65B).

As shown in FIG. 62 , FIG. 63 , FIG. 65A, and FIG. 65B, the third coverwall portion 429 extends downward from the second opposing side portion426 d. The shape of the projecting end portion 429 a which is an endportion of projecting side of the third cover wall portion 429 is alsoformed to have a shape being approximately same with the shape of theupper portion of the rear wall 400 of the front lateral member 396. Thethickness D5 of the third cover wall portion 429 is formed to be thickerthan the thickness D3 of the first cover wall portion 426 (refer to FIG.65B).

As shown in FIG. 62 , FIG. 63 , FIG. 65A, and FIG. 65B, the connectingwall portion 430 extends downward from one side portion 426 a of thefirst cover wall portion 426, and connects the second cover wall portion428 and the third cover wall portion 429 to each other. The connectingwall portion 430 extends in a direction substantially orthogonal to thefirst cover wall portion 426. An arcuate cutout portion 432 is formed ina central portion between the second cover wall portion 428 and thethird cover wall portion 429 in the connecting wall portion 430. Thethickness D6 of the connecting wall portion 430 is formed to be the samethickness as the thickness D3 of the first cover wall portion 426 (referto FIG. 65A).

As shown in FIG. 62 , FIG. 63 , FIG. 65A, and FIG. 65B, the reinforcingrib wall 431 is provided between the second cover wall portion 428 andthe third cover wall portion 429. In the present embodiment, thereinforcing rib wall 431 is provided at the center portion between thesecond cover wall portion 428 and the third cover wall portion 429. Asshown in FIG. 62 , the reinforcing rib wall 431 has a first connectingedge 431 a connected to the first cover wall portion 426 and a secondconnecting edge 431 b connected to the connecting wall portion 430. Asshown in FIG. 65B, the thickness D7 of the reinforcing rib wall 431 isformed thicker than the thickness D3 of the first cover wall portion426. In addition, the wall thickness D7 of the reinforcing rib wall 431is formed to have the same thickness as the thickness D4 of the secondcover wall portion 428 and the wall thickness D5 of the third cover wallportion 429.

As shown in FIG. 61 , under the state where the floor mat 32 is laid,the other side portion 426 b of the first cover wall portion 426 islocated at the upper end side of the rear wall 400, and contact to aposition higher than the upper end of the first cutout portion 417. Inaddition, in the second cover wall portion 428, the projecting endportion 428 a contacts to the rear wall 400 at the machine outward sideof the first cutout portion 417. Also, in the third cover wall portion429, the protruding end portion 429 a is in contact with the rear wall400 at a the machine inward side of the first cutout portion 417. Inreinforcing rib wall 431, the end portion of the side of the other sideportion 426 b contacts to the upper portion 400 a of the rear wall 400.The first cover wall portion 426, the second cover wall portion 428, andthe third cover wall portion 429 are brought into contact with the frontlower frame 52, so that the first covering portion 421 is held and theupper portion of the first cutout portion 417 is covered (closed) withthe first covering portion 421. That is, the first cover wall portion426, the second cover wall portion 428, and the third cover wall portion429 are held by contacting to a side of the cover target portion (thefirst cutout portion 417 and the second cutout portion 418) and close(cover) the covering target portion under the state where the hingeportion 427 elastically bends and the first cover wall portion 426 isswung upward.

In the present embodiment, the second cover wall portion 428 and thethird cover wall portion 429 are mainly in contact with a portioncontacting to the upper portion 400 a of the rear wall 400 so as topress the upper portion 400 a, and are in contact with the lower portion400 b and the stepped portion 400 c in a shape fitting to the shapesthereof.

As shown in FIG. 61 , the upper portion of the bolt 413 and the thirdnut 416 are inserted into the cutout portion 432 of the connecting wallportion 430 under the state where the first covering portion 421 closesthe first cutout portion 417, and thereby preventing interference withthem.

Meanwhile, the second covering portion 422 also has a first cover wallportion, a hinge portion, a second cover wall portion, a third coverwall portion, a connecting wall portion, and a reinforcing rib wallsimilar to those of the first covering portion 421.

As can be known from FIG. 61 and FIG. 62 , the lower portion of thefirst cutout portion 417 is covered (closed) with the firstforward-placing portion 423L, the second forward-placing portion 424L,and a portion (a mat main body 420) extending from the firstforward-placing portion 423L to the second forward-placing portion 424L.In addition, the lower portion of the second cutout portion 418 iscovered (closed) with the first forward-placing portion 423R, the secondforward-placing portion 424R, and a portion (the mat main body 420)extending from the first forward-placing portion 423R to the secondforward-placing portion 424R.

In the present embodiment, the floor mat 32 includes a floor portion 419and a wall portion (a front lateral member 396) disposed at the floorportion 419 and a circumferential edge portion of the floor portion 419,the mat main body 420 laid on the floor portion 419, that is, the matmain body 420 laid on the working machine 1 having an opening portion(the first cutout portion 417, the second cutout portion 418) at a partof portion connecting to the floor portion 419 of the wall portion, acovering portion (the first covering portion 421, the second coveringportion 422) for closing the opening portion, and a connecting portion(the hinge portion 427) for bendably connecting the covering portion tothe circumferential portion (the extended portion 420 c) of the mat mainbody 420. The covering portion includes the first cover wall portion 426having the side portion 426 a attached to the attachment portion 427,and a first opposite side portion 426 c and a second opposite sideportion 426 d each extending from end portions of the side portion 426 aand being opposite to each other, a second cover wall portion 428extending downward from the first opposite side portion 426 c, and thethird cover wall portion 429 extending downward from the second oppositeside portion 426 d. A length of the second cover wall portion 428 from aportion connecting to the first opposite side portion 426 c to a lowerend portion of the second cover wall portion 428 is equal to or lessthan a thickness of the mat main body 420, and a length of the thirdcover wall portion 429 from a portion connecting to the second oppositeside portion (426 d) to a lower end portion of the third cover wallportion 429 is equal to or less than the thickness of the mat main body420.

According to the above configuration, by bending the covering portionwith respect to the mat main body 420 at the connecting portion, theopening portion can be closed. In addition, the height of the secondcover wall portion 428 in the non-bent state (the length from theportion connecting to the first opposing side portion 426 c to the lowerend portion) and the height of the third cover wall portion 429 (thelength from the portion connecting to the second opposing side portion426 d to the lower end portion) is equal to or less than the thicknessof the mat main body 420, so that the covering portion for closing theopening portion (the covering target portion) can be formed on the matmain body 420 without increasing a total thickness of the floor mat 32.

Further, the connecting portion is thinner than the thickness of thecircumferential edge portion of the mat main body 420 and the thicknessof the first cover wall portion 426.

In this manner, the covering portion can be easily bent with respect tothe mat main body 420.

In addition, the connecting wall portion 430 extends downward from oneside portion 426 a of the first cover wall portion 426 and connects thesecond cover wall portion 428 and the third cover wall portion 429 onone side 426 a.

In this manner, it is possible to improve the strength of the coveringportion (the first covering portion 421, the second covering portion422).

Provided with the reinforcing rib wall 431 having the first connectingedge 431 a arranged between the second cover wall portion 428 and thethird cover wall portion 429 and connected to the first cover wallportion 426, and the second connecting edge 431 b connected to theconnecting wall portion 430.

In this manner, the strength of the covering portion (the first coveringportion 421, the second covering portion 422) can be further improved.

The thickness D4 of the second cover wall portion 428 and the thicknessD5 of the third cover wall portion 429 are thicker than the thickness D3of the first cover wall portion 426.

According to the above configuration, the strength of the coveringportions (the first covering portion 421 and the second covering portion422) can be further improved. In this manner, for example, even in thecase where the operator steps on the first cover wall portion 426 withthe foot, the second cover wall portion 428 and the third cover wallportion 429 can firmly support the first cover wall portion 426.

In addition, the working machine 1 according to the present embodimentis provided with the floor mat 32 described above, and the coveringmember is bent upward at the connecting portion with respect to the matmain body, and thereby closing the opening portion.

According to the above configuration, the covering portion for closingthe opening portion can be provided in the mat main body 420 withoutincreasing the total thickness of the floor mat 32.

In addition, the working machine includes the cabin 5 having the floorportion 419 and the wall portion (the front lateral member 396), andfront mount members 48 and 49 for supporting a front portion of thecabin 5. The cabin 5 has the first front pillar portion 77 and a secondfront pillar portion 78 provided at a distance from the first frontpillar portion 77 in the machine width direction K2. The wall portionincludes the opening portion (the first cutout portion 417, the secondcutout portion 418) provided between the lower end portions of the firstfront pillar portion 77 and the second front pillar portion 78 andcutout at portions corresponding to the front mount members 48 and 49.

In this manner, the noise can be prevented from propagating to theinterior 5A of the cabin 5 through the opening portion.

In the above description, the embodiment of the present invention hasbeen explained. However, all the features of the embodiment disclosed inthis application should be considered just as examples, and theembodiment does not restrict the present invention accordingly. A scopeof the present invention is shown not in the above-described embodimentbut in claims, and is intended to include all modifications within andequivalent to a scope of the claims.

What is claimed is:
 1. A working machine, comprising: a traveling frameprovided with a top plate having an opening; a swivel base arranged onthe traveling frame and configured to be turned about center of theopening as a turn axis; and a swivel joint arranged at the center of theopening, wherein the top plate includes: a first joint support portionprotruding toward the center of the opening and supporting the swiveljoint; and a second joint support portion protruding toward the centerof the opening from a position opposite to, across the center, the firstjoint support portion and supporting the swivel joint, wherein the firstjoint support portion has a first opening portion penetrating from anupper surface to a lower surface of the first joint support portion,wherein the second joint support portion has a second opening portionpenetrating from an upper surface to a lower surface of the second jointsupport portion, wherein the swivel joint includes a first fixingportion and a second fixing portion, the first fixing portion protrudingin one horizontal direction, the second fixing portion protruding in anopposite horizontal direction that is opposite to the one horizontaldirection, wherein the first joint support portion includes a first baseportion and a first attachment portion which has the first fixingportion placed and attached thereon, the first base portion extendingfrom a circumferential edge of the opening to a midway portion of thefirst joint support portion in a direction in which the first jointsupport portion protrudes the first attachment portion extending fromthe first base portion to a distal end portion of the first jointsupport portion in the direction in which the first joint supportportion protrudes, wherein the second joint support portion includes asecond base portion and a second attachment portion which has the secondfixing portion placed and attached thereon, the second base portionextending from the circumferential edge of the opening to a midwayportion of the second joint support portion in a direction in which thesecond joint support portion protrudes, the second attachment portionextending from the second base portion to a distal end portion of thesecond joint support portion in the direction in which the second jointsupport portion protrudes, wherein the first opening portion is in thefirst base portion, and wherein the second opening portion is in thesecond base portion.
 2. The working machine according to claim 1,further comprising a turning motor attached to the swivel base; a swingbearing having an outer ring attached to the swivel base, and an innerring provided on an inner peripheral side of the outer ring so as to berotatable around the turn axis, the inner ring having an innerperipheral gear portion formed on an inner peripheral side thereof; anda pinion meshing with the inner peripheral gear portion and moving alongthe inner peripheral gear portion by being driven to rotate by theturning motor, wherein the traveling frame has an inner ring attachmentportion shaped annularly to which the inner ring is attached, whereinthe first joint support portion and the second joint support portionprotrude from the inner ring attaching portion toward the center of theopening, and wherein the first opening portion and the second openingportion are provided below a movement locus of the pinion.
 3. Theworking machine according to claim 1, further comprising: a swingbracket having a rotation support portion rotatably supported on theswivel base so as to be rotatable about a vertical axis; a hydraulichose disposed through the swing bracket; a hose retainer for retainingthe hydraulic hose; a holder bracket attached to the swing bracket; anda fastener for attaching the hose retainer to the holder bracket, thefastener having fastening operation portions that face the rotationsupport portion in a state where the fastener is attached to the holderbracket.
 4. The working machine according to claim 3, wherein the holderbracket has an attachment stay portion attached to the rotation supportportion from above.
 5. A working machine, comprising: a traveling frameprovided with a top plate having an opening; a swivel base arranged onthe traveling frame and configured to be turned about center of theopening as a turn axis; and a swivel joint arranged at the center of theopening, wherein the top plate includes: a first joint support portionprotruding toward the center of the opening and supporting the swiveljoint; and a second joint support portion protruding toward the centerof the opening from a position opposite to, across the center, the firstjoint support portion and supporting the swivel joint, wherein the firstjoint support portion has a first opening portion penetrating from anupper surface to a lower surface of the first joint support portion,wherein the second joint support portion has a second opening portionpenetrating from an upper surface to a lower surface of the second jointsupport portion, wherein the swivel joint has a first fixing portionprojecting in one direction in a horizontal direction and a secondfixing portion projecting in another horizontal direction opposite tothe one direction, wherein the first joint support portion has: a firstattachment portion on which the first fixing portion is mounted; and afirst base portion gradually widening in a direction away from the firstattachment portion, the second joint support portion has: a secondattachment portion on which the second fixing portion is mounted; and asecond base portion gradually widening in a direction away from thesecond attachment portion, wherein the first opening portion is providedon the first base portion and gradually widened in the direction awayfrom the first attachment portion, and wherein the second openingportion is provided in the second base portion and gradually widelyformed in the direction away from the second attachment portion.